Trumpeting his administration's crackdown on illegal immigration and violent crime, President Donald Trump came to Long Island today to dedicate his administration's full support to police officers battling MS-13.

He left Washington early in the afternoon with his warring senior advisors, White House Chief of Staff Reince Priebus and Communications Director Anthony Scaramucci, in tow.

Trump spoke Suffolk County Community College in Brentwood, New York, close to where the ultra-violent street gang has committed a string of gruesome murders, including the massacre of four young men in April in a Central Islip park.

'These are animals,' Trump said of gang that brutalizes its victims before it kills them.

The president also gave police officers permission to be 'rough' with members of the gang - endorsing police brutality when it comes to handling 'thugs.'

And while members of the audience laughed and applauded Trump's comments, the Suffolk County Police Department hit back on Twitter after the speech.

'The SCPD has strict rules & procedures relating to the handling of prisoners. Violations of those rules are treated extremely seriously,' the police force tweeted.

'As a department, we do not and will not tolerate roughing up of prisoners.'

Trumpeting his administration's crackdown on illegal immigration and violent crime, President Donald Trump came to Long Island today to dedicate his administration's full support to police officers battling MS-13

Trump spoke Suffolk County Community College in Brentwood, New York, close to where the ultra-violent street gang that has committed a string of gruesome murders. He's seen boarding Air Force One this afternoon in Washington

He left Washington early in the afternoon with his warring senior advisors, White House Chief of Staff Reince Priebus and Communications Director Anthony Scaramucci, in tow

After his speech encouraging the 'rough' treatment of prisoners, the Suffolk County Police Department hit back on Twitter

Trump continued his tough talk on immigration and immigrant crime, which he said his administration is 'nipping in the bud,' and thanked Congress for dedicating more funding to border enforcement in a speech to law enforcement officers and the family members of crime victims.

'When you see these thugs being thrown into the back of the paddy wagon, you just see them thrown in, rough, I said, "Please don't be too nice," ' Trump recounted to laughter. 'Like when you guys put somebody in the car, and you're protecting their head, you know the way you put you're their hand over? Like don't hit their head, and they just killed somebody? Don't hit their head?'

To cheers and applause, the president told them, 'I said, "You can take the hand away, OK?" '

Trump has made cracking down on MS-13, also called Mara Salvatrucha, a top priority of his administration.

The gang, which is believed to have originated in immigrant communities in Los Angeles in the 1980s and then entrenched itself in Central America when its leaders were deported, is infamous for its violent tactics, including torturing victims and hacking them with machetes.

'They kidnap. They extort. They rape and they rob. They prey on children. They shouldn't be here. They stop on their victims. They beat them with clubs. They slash with machetes, and they stab them knives,' Trump said on Friday.

The president said the gang has 'transformed peaceful parts and beautiful, quiet neighborhoods into blood stained killing fields.

'They're animals,' he repeated. 'We cannot tolerate, as a society, the spilling of innocent, young wonderful, vibrant people. Sons and daughters, even husbands and wives. We cannot accept this violence one day more. Can't do it.'

Because of the law enforcement officers surrounding him, Trump said the people of Long Island wouldn't have to put up with the killing any more.

'You're not going to allow it to happen, and we're backing you up 100 percent. Remember that,' he said.

Trump is asking Congress to provide funding for 10,000 new immigration agents.

The House of Representatives passed legislation yesterday that authorizes $1.6 billion in spending for Trump's border wall. Senators were busy debating Obamacare until the wee hours of last night.

Trump made the funding for his barrier sound like a done deal on Friday, despite the discrepancy.

'We will build the wall, that I can tell you,' he said. 'The wall is vital and vital as a tool for ending the humanitarian disaster brought, and really brought on by drug smugglers.'

The president gave police officers permission to be 'rough' with members of the gang - endorsing police brutality when it comes to handling 'thugs'

'When you see these thugs being thrown into the back of the paddy wagon, you just see them thrown in, rough, I said, "Please don't be too nice," ' Trump recounted to laughter

'Like when you guys put somebody in the car, and you're protecting their head, you know the way you put you're their hand over? Like don't hit their head, and they just killed somebody?' To cheers and applause, the president told them, 'I said, "You can take the hand away, OK?" '

Trump's Justice and Homeland Security departments have made targeting the gang a top priority.

Its recruits are middle- and high-school students, predominantly in immigrant communities, who are said to risk violent retribution if they leave. Authorities estimate the group has tens of thousands of members across several Central American countries and many U.S. states.

Attorney General Jeff Sessions has directed his department's law enforcement agencies and federal prosecutors across the country to prioritize their prosecution, as directed by an executive order Trump signed in February, among other measures.

'We're liberating our towns and we're liberating our cities. Can you believe we have to do that?' Trump said at an Ohio rally earlier this week, adding that law enforcement agents were rooting out gang members - and 'not doing it in a politically correct fashion. We're doing it rough.'

'Our guys are rougher than their guys,' he bragged.

Trump made the same boast again today.

'I’m talking about liberating our towns. This is like I’d see in a movie: They're liberating the town, like in the old Wild West, right?' he said. 'I never thought I’d be standing up here talking about liberating the towns on Long Island where I grew up, but that's what you’re doing.'

The president said once again that US immigration services employs 'rough guys.'

'They're rough. I don't want to be -- say it because they’ll say that's not politically correct,' he added. 'You're not allowed to have rough people doing this kind of work...Just like they don't want to have rich people at the head of Treasury, okay?'

'Like, I want a rich guy at the head of Treasury, right? Right?' he told them.

The president said once again that US immigration services employs 'rough guys.' 'They're rough. I don't want to be -- say it because they’ll say that's not politically correct'

Trump was accompanied on the trip by senior policy advisor Stephen Miller, United States ambassador to the United Nations Nikki Haley and acting ICE director Tom Homan, in addition to Priebus and Scaramucci.

Scaramucci dropped off in New York, though, and did not fly back to Washington.

Attorney General Sessions was not on the trip with Trump to New York today.

The cabinet official who's on the outs with the president was in El Salvador today to give an address at an international law enforcement academy graduation near the MS-13 headquarters.

Sessions met Thursday with his Salvadoran counterpart and members of an international anti-gang task force.

'MS-13 is based here in El Salvador, but its tentacles reach across Central America, Europe, and through 40 U.S. States, and to within yards of the U.S. Capitol,' he told graduating cadets on Friday.

'With more than 40,000 members worldwide-including 10,000 in the United States-MS-13 threatens the lives and wellbeing of each and every family anywhere they exist and everywhere they infest.'

Since the beginning of January the Department of Homeland Security's investigative unit has arrested 3,311 gang members across the country in a number of targeted operations, said Homan, the acting director of U.S. Immigration and Customs Enforcement.

The agency could not provide numbers for a similar timeframe in 2016.

In this April 19, 2017 file photo, the casket of Justin Llivicura, 16, is carried from St. Joseph the Worker Church after Llivicura's funeral in East Patchogue, N.Y. Llivicura was one of four young men found slain in a suspected MS-13 gang massacre in a park in Central Islip, N.Y.

Congressman Peter King, who represents Brentwood was also on Air Force One with the president from Washington.

He said before the event that Trump's appearance would send a signal to communities that have been shaken by the violent killings.

'It's absolutely devastating. And almost all of these killings have occurred in my district, within 20 minutes of my home,' he said.

King said the gang is responsible for 17 murders between January 2016 and April 2017 in his district - but that the impact on largely immigrant communities has been larger because of the way the gang kills.

In addition to torturing victims, King said, members have also sent video of gruesome crime scenes to their victims' loved ones.

'This gang's chilling motto is 'mata, viola, controla,'which means "kill, rape and control," 'said Robert Hur, a top official at the Justice Department. 'They seek to live up to this motto through truly shocking acts of violence designed to instill fear: vicious machete attacks, execution-style gunshots, gang rape and human trafficking.'

The Trump administration blames the gang's recent resurgence in certain areas on illegal immigration and believes policies like building a wall along the southern border and cracking down on so-called 'sanctuary cities' will eradicate the problem.

Critics see the focus misplaced, however, and argue resources could be better spent on other enforcement efforts.

Trump said Friday that he'd talked to police unable to do their jobs, 'because they have a pathetic mayor or a mayor who doesn't know what's going on.'

'It’s sad. It’s sad. You look at what’s happening, it’s sad. But hopefully -- certainly in the country, those days are over,' he said. 'From now on, we’re going to enforce our laws, protect our borders, and support our police like our police have never been supported before.'