A senior counter-terrorism officer has hit back at US presidential hopeful Donald Trump after he accused British Muslims of "absolutely not reporting" suspected terrorists.

The front-runner for the Republican nomination told ITV's Good Morning Britain that Muslim communities were not doing enough to prevent attacks like the carnage in Brussels.

"When they see trouble they have to report it. They are not reporting it. They are absolutely not reporting it and that is a big problem," he told the programme's presenter Piers Morgan.

But deputy assistant commissioner Neil Basu from the UK Counter Terrorism Policing Network said the comments by the tycoon-turned politician risked playing into the hands of the terrorists by demonising the very people the police needed to help them.

"He is wrong," he told the BBC Radio 4 programme.

"There is a generational problem here. Without a doubt we have to encourage more reporting from the Muslim community and from all communities, because unlike in some other places in the world we do have integrated communities and we have people living side by side.

"If we demonise one section of the community that is the worst thing we can do, we are absolutely playing into the terrorists' hands of making people feel hate."

Mr Basu warned that the such comments could lead to a surge in hate crimes against Muslims.

"When events like this happen in Brussels and Paris very unfortunately we do see a spike in hate crime," he said.

"We don't want that to happen in our communities, we want people to feel safe and confident to come forward to the police and report what they have to report."

More than half a million people signed a petition calling for Mr Trump to be banned from the UK after he demanded a block on Muslims entering the US and claimed parts of London were "so radicalised" police were "afraid for their own lives".

He told Good Morning Britain: "I would hit Isis (another name for Islamic State) so hard you wouldn't believe it and I would get the people over there to put up their soldiers because it's about time that somebody did it.

"But I would have such back-up like you've never seen before in terms of air power, air strikes etc."

"It's like they are protecting each other but they are really doing very bad damage," Mr Trump said, complaining about the failure to turn in those who went on to launch a deadly attack in San Bernardino, California.

"They have to open up to society, they have to report the bad ones. And, you know, if you report the bad ones, all of a sudden you are not going to have the problems," he said.

Mr Trump denied he was racist, telling the programme: "I'm not 'anti' anything; I'm just common sense, I say it like it is.

"I have great respect for Muslims, I have many friends that are Muslims. I am just saying there is something with a radicalised portion that is very, very bad and very dangerous."

He said he was astounded at the failure of anyone to turn in Salah Abdeslam, the chief suspect in the Paris terror attacks who was holed up in his own neighbourhood in the Belgian capital.

"There is something wrong, and we have to get to the bottom of it, when someone like who was just captured was really coddled and taken care of by people that live in the neighbourhood.

"Many people knew he was there yet he was the number one fugitive in the world. Everybody from that area knew he was there and nobody turned him in.

"There's something going on and there's something wrong. You know it, Piers, and so do I."

He went on: "I knew Brussels years ago. I was there probably three or four times and it was so beautiful, so secure and so safe. Now it's an armed camp," he said.

"It's like a different world, a different place, there is no assimilation.

"What's going on there and what's going on in many other locations - like Paris and others - is a disgrace, an absolute disgrace that we allowed to happen."

He rejected Prime Minister David Cameron's claim that his call to ban Muslims risked aiding extremists by sowing division.

"All you have to do is look at the cities where there's been a large inflow and something's different," he said.

"There is very little assimilation for whatever reason ... they want to go by their own sets of laws."

Mr Trump told Mr Morgan - who said he considered the billionaire "a good friend" he had known for a decade - that he did not believe many people in the UK were scared of the idea of him in the White House.

"I don't think too many are. Honestly, I'm a very normal person. I happen to be intelligent, very intelligent, I guess, based on certain results that I get in doing things," he said.

"I am a person that just wants to see things run properly. I don't want to see people hurt."

Miqdaad Versi, assistant secretary-general of the Muslim Council of Britain said Mr Trump's claims were "just not true".

He told Good Morning Britain: "What we have to recognise is when some of these statements are made that fuel this idea of bigotry and really fuel the thing that terrorists themselves want - that Muslims are apart from the West and cannot be seen as equal citizens - these things are not good for our society."