President Donald Trump told a crowd of police officers Friday not to be “too nice” to suspected gang members and others under arrest.

“When you see thugs being thrown into the back of a paddy wagon, you just see them thrown in; rough. I said, ‘please don’t be too nice,'” Trump said Friday at a Suffolk County, New York event discussing the administration’s efforts to handle a violent gang known as MS-13. “Like when you guys put somebody in the car and you’re protecting their head, you know, the way you put your hand over it. Like, don’t hit their head, and they’ve just killed somebody. I said, you can take the hand away, O.K.?.”

Some in the crowd cheered at Trump’s remarks. But on social media, some observers were quick to accuse the President of encouraging violent behavior among officers at a time when police departments nationwide are under pressure to clamp down on officer-involved incidents.

President Trump appeared before federal, state, and local law enforcement officers Friday to discuss his administration’s ongoing efforts to rid the country of illegal immigrants, particularly members of the MS-13 gang. Police say the gang has been responsible for 17 killings on Long Island since January of 2016.

“They kidnap, they extort, they rape, and they rob. They prey on children. They shouldn’t be here,” President Trump said of MS-13, which first arose in Los Angeles. “They are animals.”

“We cannot accept this violence one day more,” Trump continued. “You’re not going to allow it and we’re backing you up one hundred precent.”

Trump said the administration’s goal was to “dismantle, decimate, and eradicate” MS-13 and other criminal groups operating in the U.S. But immigration advocates have expressed concern that the President’s rhetoric and targeting of undocumented immigrants writ large has in actuality emboldened gang members and spread fear among law-abiding undocumented immigrants.

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