Claims authorities won't approach someone with a 'massive bomb on his back' because of concerns about profiling

Says rival Hillary Clinton 'wants hundreds of thousands of people to pour into this country and we have no idea who they are'

Says campaign against ISIS is too 'gentle' and there is a need to 'hit them much harder over there'

Trump spoke after a bomb exploded in Chelsea and another unexploded device was discovered in Manhattan, while authorities raided a site in New Jersey

References New York bomb: 'I knew this was going to happen'

Says local police are 'afraid to do anything about it'

Says attacks will happen 'perhaps more and more all over the country'

Republican Donald Trump is warning of a spike in terror attacks after a bomb placed under a dumpster in Chelsea exploded over the weekend, and is placing blame for the attack squarely on immigrants he called a 'vicious' threat.

'They’re here. We’re letting tens of thousands of people flow into this country,' Trump said Monday morning.

'They’re bringing in many cases vicious cancer from within. This is something that’s going to be so tough. And you know they stay together so nobody really knows who it is, what’s happening. They’re plotting. This has been going on for so long everybody knows it,' Trump said.

Trump spoke just as the media announced authorities were looking for 28-year-old Ahmad Khan Rahami, a naturalized U.S. citizen born in Afghanistan in connection with the bombing.

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Republican presidential Donald Trump warned that terrorism 'is only going to get worse' and renewed his call for an immigration clamp-down in the wake of a bomb that exploded in New York over the weekend

Asked about the bombing, which governor Andrew Cuomo has said isn't linked to international terrorism although he said Monday may have a 'foreign connection,' the candidate placed the blame squarely on dangerous immigrants, as well as his rivals.

'Well it’s a mess and it’s a shame. We’re going to have to be very tough. I think maybe we’re going to be seeing a big change over the last couple of days,' Trump told 'Fox and Friends' in a call-in appearance.

'I think this is something that maybe will happen perhaps more and more all over the country,' Trump predicted.

'This is only going to get worse. This isn't going to get better,' he warned.

Trump linked the bombing, which authorities continued to pursue with what ABC reported was a police raid in New Jersey Monday morning, with American weakness and with policies that allow migration from the Middle East.

'Yeah because we’ve been weak. Our country’s been week. We’re letting people in by the thousands and tens of thousands,' Trump said.

'They can’t be properly vetted. There’s no way,' said Trump, who during his campaign has called for a temporary ban on Muslims but in a recent policy speech described a plan that would bar immigration from countries linked to terrorism until they could be properly vetted.

Trump tweeted about the attack on Sunday

Trump said the attack showed the

'We’re not winning the war. They’re winning the war,' Trump said of the campaign against ISIS

Trump immediately turned to the rise of ISIS.

'If we would have taken them out, we wouldn’t have it. They’re very strong. They’re in 28 countries right now,' he said. 'This was started by Hillary Clinton and her policies and Obama, when they got out of Iraq. This is what happened. This is a remnant of it. And it’s much more than a remnant,' Trump said.

He said of the U.S. strategy overseas, which has included deployment of air power from an international coalition fighting in Iraq and Syria, 'We’re not knocking them. We’re hitting them once in a while. We’re being very gentle about it.'

'We’re not winning the war. They’re winning the war.'

Trump got pressed repeatedly by his normally non-confrontational hosts to more carefully define what he meant his policy would be by getting 'tough' with ISIS.

'These are sick, evil people that want to destroy this country,' Trump said. 'The way we coddle them and the way we’re afraid to say anything and we’re afraid to say what the problem is and who they are and they don't want to say radical Islam,they don’t want to talk about radical Islam.'

Donald Trump got pressed repeatedly Monday about what he meant by getting 'tough' with ISIS

Pressed again about what he meant, Trump responded: 'We’re going to have to hit them much harder over there.'

'You have to stop 'em from coming into the country,' Trump said.

Trump got pressed a third time during the interview about what he would do. Trump said, 'We’re gonna have to do something extremely tough over there.'

'Like what?' asked host Steve Doocy. 'Like knock the hell out of them,' Trump said.

Trump tweeted on Sunday, 'Under the leadership of Obama & Clinton, Americans have experienced more attacks at home than victories abroad. Time to change the playbook!'

Referencing the weekend attack in a Minnesota mall, Trump said: 'The guy in Minnesota is going around screaming his famous words and knifing people and slashing people, viciously slashing people. Just crazy. How they came into the country in the first place is beyond belief. They’re here.'

Trump issued a call for 'profiling,' which he said happened in Israel but doesn't occur here.

'You have to stop them from coming into the country,' Trump said.

He repeated his claim that immigrants could be a 'Trojan Horse.'

'They’re bringing in many cases vicious cancer from within. This is something that’s going to be so tough. And you know they stay together so nobody knows what’s happening. They’re plotting.'

Trump referenced the bomb attack in New York attack Sunday and linked it to his campaign's call for change

Trump also responded to criticism that he announced that the attack was a bombing before law enforcement had revealed exactly what happened during the weekend explosion that caused terror in the streets but luckily only injuries and no fatalities.

'I was criticized for calling it correctly. What I said was exactly correct. I should be a newscaster because I called it before the news,' Trump said.

Trump accused rival Hillary Clinton of endangering the country with her own policy of allowing refugees fleeing the civil war in Syria to migrate here.

'Hillary Clinton wants to allow hundreds of thousands of these same people – they have such hatred and sickness in their hearts .. and she wants to allow hundreds of them,' Trump said. 'She wants more of them to come in.'

He continued: 'She’s trying to prove that she’s more liberal than Bernie sanders, okay? She wants hundreds of thousands of people to pour into this country and we have no idea who they are.'

During his remarks about profiling, Trump pointed to Israel, but contrasted tactics to how local police operate. 'Our local police, they know who a lot of people are – they’re afraid to do anything about it,' he said. 'They don’t want to be accused of profiling.'

Trump added: 'Do we have a choice? Look what’s going on.'

'We're allowing these people to come into our country and destroy our country and make it unsafe for people. We're allowing these people to come in,' Trump said.