President Donald Trump has repeatedly said he would take a hard line on immigration and crime.
He recently celebrated a move in that direction after sending more than 250 people to a prison with a brutal reputation.
Over 250 alleged criminals were deported to El Salvador’s mega prison, a facility known for holding Venezuelan gang members and convicted mass murderers.
The complex, called the Center for Terrorism Confinement, is thought to be the largest prison in the Americas and can hold up to 40,000 inmates.
To carry out the deportations, the administration invoked a little-known wartime statute that dates back to the 18th century.
That law is the Alien Enemies Act of 1798, which had previously been cited during World War II to justify internment of Japanese, German and Italian nationals.
A federal judge moved to block the deportations, but officials say the plane was already in the air when the court issued its ruling.
When he took office again, Trump signed an executive order asserting the US faced an “invasion” of immigrants tied to organized crime.
The administration said that order provided legal cover to apply the 1798 law.
CNN’s David Culver visited the prison and described the conditions as stark and spartan.
Culver and his team reported that many cells are constructed to hold 80 inmates or more.
They also said detainees spend about 23.5 hours a day inside their cells.
Culver wrote: “The only furniture is tiered metal bunks, with no sheets, pillows or mattresses … an open toilet, a cement basin and plastic bucket for washing and a large jug for drinking water.”
Officials believe the facility currently houses between 10,000 and 20,000 prisoners.
The 261 people flown from the US are thought to be the most recent arrivals.
Of the 261 people deported, 238 are alleged to have links to the Venezuelan gang Tren de Aragua.
The remaining 23 are accused of membership in MS-13.
Journalists on site said inmates find no privacy or comfort inside the cells.
The reporting team added: “They do not work. They are not allowed books or a deck of cards or letters from home.
“Plates of food are stacked outside the cells at mealtimes and pulled through the bars. No meat is ever served.
“The 30-minute daily respite is merely to leave the cell for the central hallway for group exercise or Bible readings.”
Critics argue the treatment breaches prisoners’ civil liberties.
But the El Salvadoran government says its tough approach to gang-affiliated criminals has improved public safety.