British laws restricting what the police can say about criminal cases are “not fit for the social media age,” a government committee said in a report released Monday in Britain that highlighted how unchecked misinformation stoked riots last summer.

Violent disorder, fueled by the far right, affected several towns and cities for days after a teenager killed three girls on July 29 at a Taylor Swift-themed dance class in Southport, England. In the hours after the stabbings, false claims that the attacker was an undocumented Muslim immigrant spread rapidly online.

In a report looking into the riots, a parliamentary committee said a lack of information from the authorities after the attack “created a vacuum where misinformation was able to grow.” The report blamed decades-old British laws, aimed at preventing jury bias, that stopped the police from correcting false claims.

By the time the police announced the suspect was British-born, those false claims had reached millions.

The Home Affairs Committee, which brings together lawmakers from across the political spectrum, published its report after questioning police chiefs, government officials and emergency workers over four months of hearings.

Axel Rudakubana, who was sentenced to life in prison for the attack, was born and raised in Britain by a Christian family from Rwanda. A judge later found there was no evidence he was driven by a single political or religious ideology, but was obsessed with violence.

Karen Bradley, the Conservative Party lawmaker who leads the Home Affairs Committee, said “bad-faith actors” exploited the attack. But she added that a lack of accurate information allowed lies to proliferate.

“By failing to disclose information to the public,” she said, “false claims filled the gap and flourished online, further undermining confidence in the police and public authorities.”

The committee’s report pinpointed two false claims that were shared on X. One, posted about two hours after the attack, claimed the suspect was a “Muslim immigrant.” It received more than 3.8 million views.

The second, posted about five hours afterward, falsely suggested the suspect was an asylum seeker named “Ali-Al-Shakati” who was on an “MI6 watch list.” The post received about 27 million views on X within a day. Merseyside Police, the local force investigating the attack, did not announce that the name was wrong until midday July 30.

Hours later, the first riot broke out in Southport. The disorder continued in multiple towns and cities, and many protests targeted mosques and hotels housing asylum seekers. Two buildings were set on fire while people were inside. More than 300 police officers were injured during the riots, and the response cost the police an estimated 28 million pounds, or about $36 million, the report said.

It added that Merseyside Police “were put in a very difficult position” because they were legally barred from disclosing the suspect’s identity and received “inconsistent advice” from prosecutors about whether they could confirm he was not Muslim.

The committee’s report acknowledged that it was impossible to determine “whether the disorder could have been prevented had more information been published.”

But it concluded that the lack of information after the stabbing “created a vacuum where misinformation was able to grow, further undermining public confidence,” and that the law on contempt was not “fit for the social media age.”

In Britain, a law bans the naming of suspects under 18 unless a judge makes an exception. Mr. Rudakubana was 17 at the time of the attack. Another law, designed to protect the right to a fair trial, bans the publication of information that could influence a jury. That rule, part of the 1981 Contempt of Court Act, is lifted once a defendant is found guilty or innocent.

Serena Kennedy, Merseyside’s chief constable, told the committee that the police disclosed on the evening of July 29 that the attacker had been born in Wales, but misinformation had already proliferated.

Ms. Kennedy said she had planned to make an announcement two days later clarifying that Mr. Rudakubana was not Muslim and that his parents were Christian. After notifying the Crown Prosecution Service, the body that brings criminal charges in England, an official told her the information should not be made public, she said.

“This case highlights why we need to look at how we handle releases of information to the public, while also making sure that we do not impact on the criminal justice trial,” Ms. Kennedy said, adding that contempt laws did not “take account of where we are in terms of the impact of social media.”

In a statement, the Crown Prosecution Service said that although an official expressed “different views” on the disclosure of Mr. Rudakubana’s religion, they did not tell the police it would bias a jury.

The statement added, “We support proposals for law reform which will make the application of contempt law clearer and simpler — especially when linked to heightened matters of general public interest such as public safety or national security.”

Since the Southport attack, the Law Commission of England and Wales has been conducting a review of the Contempt of Court Act.

A home in Austin, Texas, was leveled and at least 23 others were damaged on Sunday in an explosion of unknown causes that could be heard for miles and left six people injured, the authorities said.

The explosion happened just after 11 a.m. local time in a northwest section of Austin, according to the Austin Fire Department.

The cause of the explosion was under investigation. The authorities said there was no signs of criminal activity in connection with the explosion.

“We believe this is certainly an isolated incident,” said Division Chief Wayne Parrish of the Austin Fire Department.

He said there was no gas service to the residence but it did have propane tanks. A representative for Texas Gas Service said that crews responded on Sunday morning and “confirmed the home did not have natural gas service.”

A two-story house where the explosion happened collapsed and a neighboring home partially collapsed, the authorities said.

Two occupants of the home where the explosion occurred were taken to a hospital. One of them was in critical condition and the other was in serious condition, Capt. Shannon Koesterer of the Austin-Travis County Emergency Medical Services Department told reporters at a news conference.

An occupant in a neighboring home that was damaged was in critical condition, Captain Koesterer said. Another person had minor injuries, and two firefighters also had minor injuries, the captain added.

The authorities said they had accounted for all of the people who were in the affected residences at the time of the blast.

Officials said that garage doors and windows nearby were blown out and a car at the residence where the explosion happened caught fire. Power was out in the surrounding area because of damage from the explosion, the authorities said.

The blast could be heard as far away as Georgetown, Texas, which is about 30 miles north, Chief Parrish said.

The Police Department in Cedar Park, which is about 20 miles away, said on social media that it was aware of the “loud boom that was heard and felt throughout the city.”

Several agencies responded to the scene, including Austin-Travis County E.M.S., the Austin Police Department, the Travis County Sheriff’s Office and the F.B.I., Chief Parrish said. The Travis County fire marshal will lead the investigation, he said.

Alexandra E. Petri contributed reporting.

On the first day of Russia’s all-out invasion, President Volodymyr Zelensky of Ukraine and his main political opponent at home shook hands, setting aside their ferocious rivalry to focus on the enemy. The country’s typically raucous politics went largely dormant for the three years that followed.

Now, as peace talks led by the Trump administration have stirred prospects for a cease-fire and eventual elections, the political jockeying has returned.

Ukrainian politicians are maneuvering at home and reaching out behind the scenes to the Trump administration, which has made no secret of its disdain for Mr. Zelensky, despite his lionization on the world stage for standing up to Russia.

Petro O. Poroshenko, a former Ukrainian president and the leader of a rival party, says that the best way to smooth the peace talks is to bring opposition figures into the government.

Mr. Poroshenko had earlier floated the idea of overhauling Ukraine’s politics to form a national unity government, which could benefit his party. He revived the proposal after Mr. Zelensky’s contentious Oval Office meeting with President Trump in February and a call by a Republican senator for him to step down.

Mr. Zelensky has shown no interest in forming a coalition of ministers that would include opposition figures. Instead, his government has ratcheted up pressure on opponents by law enforcement and security agencies.

The mayor of Kyiv, Vitali Klitschko, has said Mr. Zelensky abused martial law powers to overrule the city council. In January, Ukraine’s national security council froze Mr. Poroshenko’s bank accounts while leveling no specific accusations.

“We don’t have any other option other than a coalition of national unity, a government of national unity,” Mr. Poroshenko said in an interview on Wednesday. “We should have unity in the Parliament and demonstrate unity in the country. And the results of this decision should be a stop to the war.”

Mr. Zelensky’s five-year term, which was set to expire last year, was extended under martial law. Elections are legally banned under martial law and impractical as long as Ukraine remains at war.

Nearly a month ago, Ukraine offered a monthlong, unconditional cease-fire that Russia has not accepted. A Trump administration envoy, Steve Witkoff, traveled to Russia on Friday, possibly in an effort to rekindle negotiations.

Mr. Poroshenko said that the talks could get a boost if Mr. Zelensky allowed political opponents to enter the government, given that Mr. Trump has called Mr. Zelensky a “dictator without elections.” That echoed criticism by the Russian president, Vladimir V. Putin, who has said he will not sign a peace settlement with Mr. Zelensky.

Mr. Poroshenko said he disagreed with Mr. Trump’s assessment of Mr. Zelensky as a dictator.

But with the prospect of a cease-fire and elections, Mr. Poroshenko has taken to more openly criticizing the president. The sanctions that the national security council placed on Mr. Poroshenko froze his bank accounts and could exclude him from future elections.

Mr. Poroshenko called the sanctions against him “disastrous, unconstitutional and extrajudicial.” If he were arrested, he said, he would then say that Ukraine is on a path to dictatorship.

The intense rivalry between the two Ukrainian leaders goes back years. Mr. Poroshenko led Ukraine from 2014 to 2019. After Mr. Zelensky soundly defeated him, the new government then questioned Mr. Poroshenko as a witness in a flurry of criminal cases that Mr. Poroshenko called politically motivated.

Even as tanks massed at the border before Russia invaded in 2022, the infighting continued in Ukraine: Prosecutors sought an arrest warrant for Mr. Poroshenko, though it was declined by a judge.

Mr. Poroshenko has a base of support in Ukrainian nationalist politics, particularly in western and central Ukraine, while Mr. Zelensky in the 2019 race won broad support across the country, including from Russian speakers in central and eastern Ukraine.

The two men met on the morning of Feb. 24, 2022, when Russia began its onslaught, to set aside their rivalry. Mr. Zelensky asked what he could do for Mr. Poroshenko. The former president said that he asked for 5,000 Kalashnikovs to arm his supporters against the Russians, and that Mr. Zelensky had provided the guns.

Mr. Poroshenko, 59, has little chance of winning a presidential election, polls show. He has consistently been in third place or lower, behind Mr. Zelensky and a former army commander, Gen. Valery Zaluzhny.

Political analysts say that Mr. Poroshenko may be angling for an electoral alliance with General Zaluzhny, who is serving as ambassador to Britain and is wildly popular in Ukraine. He has remained mostly silent about politics.

In the interview, Mr. Poroshenko said he had met with Mr. Zaluzhny in London, but he declined to disclose details of their talks. An aide to Mr. Poroshenko said he had accepted an autographed copy of the general’s biography, “Iron General.”

As Mr. Zelensky has negotiated with the Trump administration, Mr. Poroshenko has offered advice through intermediaries, he said.

“Trump can ask unexpected questions, I can say even impolite,” Mr. Poroshenko said.

At one meeting during the first Trump administration, Mr. Poroshenko said, Mr. Trump asked if he could get an honest answer to a question. Mr. Poroshenko said yes. Mr. Trump then leaned closer and asked, “‘Tell me, is Crimea Russian?’”

Mr. Poroshenko said he answered that Crimea, the peninsula that Russia seized in 2014, was Ukrainian, and asked what prompted the question. Mr. Trump then said that a Russian friend had told him that the peninsula should be Russian, Mr. Poroshenko said.

Mr. Poroshenko pursued a transactional foreign policy with the United States that partly paid off. That included purchases of coal from Pennsylvania that preserved some jobs in a swing state, even though Ukraine has abundant coal of its own.

Before the end of Mr. Trump’s first term, the administration offered a formal statement, known as the Crimea Declaration, that asserted as a matter of U.S. policy that Crimea was Ukrainian.

“He’s not easy,” Mr. Poroshenko said of Mr. Trump. “But now is the time of diplomacy.”

Secretary of State Marco Rubio said on Sunday that the United States had sent 10 members of two gangs — MS-13, which originated in the United States and operates in South America, and Tren de Aragua, rooted in Venezuela — to El Salvador late Saturday.

Mr. Rubio added in a social media post that “the alliance” between President Trump and President Nayib Bukele of El Salvador had “become an example for security and prosperity in our hemisphere.”

The Trump administration has sent hundreds of Venezuelans to a notorious prison in El Salvador at the invitation of Mr. Bukele, who is positioning himself as a crucial regional ally to Mr. Trump and is scheduled to meet with the president in Washington on Monday.

The administration has portrayed those deportees as violent criminals or terrorists, but court papers have shown that the evidence on which the government acted was often little more than whether they had tattoos or had worn clothing associated with the criminal organization.

Mr. Bukele has become Latin America’s most popular leader for his takedown of gangs, even as he has suspended civil liberties and been accused by U.S. prosecutors of secretly negotiating with the same gangs.

A spokeswoman for Mr. Bukele, Wendy Ramos, did not immediately respond to a request for information on the 10 deportees Mr. Rubio referred to.

In early February, Mr. Rubio announced a possible deal with Mr. Bukele, under which the Salvadoran government would hold convicted criminals in its prison system, for a fee. The administration began sending groups of detainees to El Salvador in mid-March, and has so far sent at least five flights carrying Venezuelan and Salvadoran deportees to El Salvador.

The Salvadoran government has released videos and photos showing deportees being removed from planes and marched into a prison outside the capital, San Salvador, called the Terrorism Confinement Center, or CECOT.

Some of the men have been removed from the United States under the Alien Enemies Act, a wartime power dating to 1798, while others were removed under regular U.S. immigration law and had final deportation orders, according to the administration.

The Supreme Court ruled last week that the Trump administration could continue to deport Venezuelan migrants using the Alien Enemies Act for now, overturning a lower court that had put a temporary stop to those deportations.

The decision represented a victory for the administration, though the ruling did not address the constitutionality of using the Alien Enemies Act to send the migrants to a prison in El Salvador. The justices instead issued a narrow procedural ruling, saying that the migrants’ lawyers had filed their lawsuit in the wrong court.

In a separate case, the Supreme Court ordered the administration on Thursday to take steps to return a Salvadoran man, Kilmar Armando Abrego Garcia, who was legally in the United States but was sent to the prison in El Salvador in March as a result of what officials said was an administrative error. But the administration has defied an order by the federal judge handling Mr. Abrego Garcia’s case to provide a written road map of its plans to free him, and in a hearing on Friday, repeatedly stonewalled the judge’s efforts to get the most basic information about him.

On Saturday, a State Department official, Michael Kozak, told the Maryland judge in Mr. Abrego Garcia’s case that the detainee was “alive and secure” and that, according to the U.S. Embassy in San Salvador, he was in being held in CECOT. The embassy has not responded to requests for information from The New York Times.

Following the Supreme Court’s order on Thursday, President Trump said that he would follow the directions of the court if it ordered him to “bring somebody back,” though the court’s ruling indicated that the judiciary might not have the power to require the executive branch to do so.

On Saturday, Mr. Trump wrote of the deportees on Truth Social: “These barbarians are now in the sole custody of El Salvador, a proud and sovereign Nation. And their future is up to President B and his Government.”

President Bukele, who posted a photo on social media that day indicating that he was on his way to Washington, has largely remained silent on Mr. Abrego Garcia’s case.

Eric Schmitt reported from Washington and Annie Correal from Panama City.