WASHINGTON (AP) — President Donald Trump on Wednesday signed the Laken Riley Act into law, giving federal authorities broader power to deport immigrants in the U.S. illegally who have been accused of crimes. He also announced at the ceremony that his administration planned to send the “worst criminal aliens” to a detention center in Guantanamo Bay, Cuba.

The bipartisan act, the first piece of legislation approved during Trump’s second term, was named for Riley, a 22-year-old Georgia nursing student who was slain last year by a Venezuelan man in the U.S. illegally.

“She was a light of warmth and kindness,” Trump said during a ceremony that included Riley’s parents and sister. “It’s a tremendous tribute to your daughter what’s taking place today, that’s all I can say. It’s so sad we have to be doing it.”

Trump has promised to drastically increase deportations, but he also said at the signing that some of the people being sent back to their home countries couldn’t be counted on to stay there.

“Some of them are so bad that we don’t even trust the countries to hold them because we don’t want them coming back, so we’re gonna send ’em out to Guantanamo,” Trump said. He said that he’d direct federal officials to get facilities in Cuba ready to receive immigrant criminals.

“We have 30,000 beds in Guantanamo to detain the worst criminal aliens threatening the American people,” the president said.

The White House announced a short time later that Trump had signed a presidential memorandum on Guantanamo.

The move immediately doubles U.S. detention lockup capacities, Trump said at the signing ceremony, noting that Guantanamo is “a tough place to get out of.”

In subsequent comments to reporters outside the White House, new Homeland Security Secretary Kristi Noem said of expanded detention facilities that “we’re building it out” and that the administration would seek funding via spending bills Congress is set to consider.

The administration’s border czar, Tom Homan, said U.S. Customs and Immigration Enforcement would run the facility in Cuba and that the “the worst of the worst” could go to Guantanamo.

Still, the details of Trump’s plan were not immediately clear. The U.S. military base has been used to house detainees from the U.S. war on terrorism for years.

But authorities have also detained migrants at sea at a facility known as the Migrant Operations Center on Guantanamo, a site the U.S. has long leased from the Cuban government. Many of those housed there have been migrants from Haiti and Cuba.

The Supreme Court ruled in 2008 that enemy combatants in the war on terror held without charge at the military prison at Guantanamo had the right to challenge their detention in federal court. But the justices did not decide whether the president had the authority to detain people at all.

Before Trump took office, the Democratic administrations of Barack Obama and Joe Biden worked to reduce the number of terrorism suspects held at Guantanamo.

Laken Riley was out for a run in February 2024 when she was killed by Jose Antonio Ibarra, a Venezuelan national who was in the country illegally. Ibarra was found guilty in November and sentenced to life without parole.

Ibarra had been arrested for illegal entry in September 2022 near El Paso, Texas, and released to pursue his case in immigration court. Federal officials say he was arrested by New York police in August 2023 for child endangerment and released. Police say he was also issued a citation for shoplifting in Georgia in October 2023.

The act quickly passed the newly Republican-controlled Congress with some Democratic support even though immigrant rights advocates said it possibly could lead to large roundups of people for offenses as minor as shoplifting.

The swift passage, and Trump’s signing nine days after taking office adds to the potent symbolism for conservatives. To critics, the measure has taken advantage of a tragedy and could lead to chaos and cruelty while doing little to fight crime or overhaul the immigration system.

Riley’s mother thanked Trump while holding back tears.

“He said he would secure our borders and he would never forget about Laken and he hasn’t,” she said.

Several top Republican lawmakers and Noem attended the signing ceremony, as did Democratic Sen. John Fetterman of Pennsylvania, a cosponsor.

Under the new law, federal officials would have to detain any immigrant arrested or charged with crimes such as theft or assaulting a police officer, or offenses that injure or kill someone. State attorneys general could sue the U.S. government for harm caused by federal immigration decisions — potentially allowing the leaders of conservative states to help dictate immigration policy set by Washington.

Some have questioned whether it is constitutional. Immigrant advocates are bracing for mass detentions.

“They don’t just get to celebrate. They get to use this for their mass deportation agenda,” Naureen Shah, deputy director of government affairs in the equality division of the American Civil Liberties Union, said of the act’s supporters.

The ALCU says the law can allow people to be “mandatorily locked up — potentially for years — because at some point in their lives, perhaps decades ago, they were accused of nonviolent offenses.”

Hannah Flamm, interim senior director of policy at the International Refugee Assistance Project, said the measure violates immigrants’ basic rights by allowing for detaining people who have not been charged with wrongdoing, much less convicted.

“The latent fear from the election cycle of looking soft on crime snowballed into aiding and abetting Trump’s total conflation of immigration with crime,” Flamm said.

She also noted, “I think it is pivotal to understand: This bill, framed as connected to a tragic death, is pretext to fortify a mass deportation system.”