Jan. 29 (UPI) -- President Donald Trump on Wednesday signed a presidential memorandum to use Guantanamo Bay as a migrant detention facility for "the worst criminal illegal aliens threatening the American people."

The United States retains jurisdiction over Guantanamo Bay on the southeastern end of Cuba. A United States military base is on 45 square miles.

Trump announced the expansion of the Migrant Operations Center before signing the Laken Riley Act, which add the mandatory detention of migrants to include noncitizens with burglary, larceny, theft or shoplifting. Riley was a 22-year-old nursing student murdered by an undocumented Venezuelan immigrant.

"We have 30,000 beds in Guantanamo to detain the worst criminal illegal aliens threatening the American people," he said at the ceremony in the White House. "Some of them are so bad we don't even trust the countries to hold them, because we don't want them coming back. So we're going to send them out to Guantanamo."

He added: "It's a tough place to get out of."

He described it as an executive order but is actuall was a memorandum "to halt the border invasion, dismantle criminal cartels, and restore national sovereignty."

He ordered Secretary of Defense Secretary Pete Hegseth and Homeland Security Security Secretary Kristi Noem to "take all appropriate actions to expand the Migrant Operations Center at Naval Station Guantanamo Bay to full capacity to provide additional detention space for high-priority criminal aliens unlawfully present in the United States, and to address attendant immigration enforcement needs identified by the Department of Defense and the Department of Homeland Security."

Hegseth was stationed at the facility with the Army from 2004 to 2005.

Management of a Guantanamo Bay detention facility for migrants would be overseen by Immigrations and Customs Enforcement out of Miami, Trump's top immigration advisers told CNN.

"There might be some resources that could be established for the worst of the worst at Guantanamo Bay, and that's something that he is evaluating along with our team at the Department of Homeland Security," Noem told CNN.

Currently, a relatively few migrants are housed there as they undergo interviews with asylum officers. Asylum-seekers who passed those interviews are referred for resettlement in third countries like Australia. They are not allowed into the United States.

A separate area is a post-9/11 military prison where the U.S. still holds 15 terrorism suspects. The U.S. military prison at Guantanamo was opened in January 2002 and was designated for War on Terror suspects.

In 2002, Camp X-Ray was closed and all prisoners were transferred to Camp Delta at Guantanamo Bay.

The United States seized Guantanamo Bay and established a Naval base there in 1898.

In early 1990s, thousands of Haitians were detained inside the base, including those with HIV, who were banned from entering the U.S. at the time.

Miguel Diaz-Canel, president of Cuba, wrote in Spanish on X: "In an act of brutality, the new U.S. government announces the imprisonment at the Guantanamo Naval Base, located in illegally occupied territory #Cuba, of thousands of migrants that it forcibly expels, and will place them next to the well-known prisons of torture and illegal detention."

ICA said it made 969 arrests Tuesday.