What is really going on in politics? Get our daily email briefing straight to your inbox Sign up Thank you for subscribing We have more newsletters Show me See our privacy notice Invalid Email

Donald Trump has attacked Britain's biggest police force by suggesting the "demented terrorist" behind today's Parsons Green incident was "in the sights of Scotland Yard".

The US President was branded "idiotic" and "extremely unhelpful" for his criticism of the Metropolitan Police less than four hours after a suspected terror bomb on the Tube.

He also used the incident to justify his travel ban on people from a number of Muslim nations, despite officers not revealing how many suspects there are or their identity, background, religion or nationality.

He tweeted: "Another attack in London by a loser terrorist. These are sick and demented people who were in the sights of Scotland Yard." He added: "Must be proactive and nasty."

Scotland Yard branded Trump's claims "speculation" and "unhelpful".

Asked specifically about the US President's tweets, a Metropolitan Police spokesman told the Mirror: “This is a live investigation. We will provide further updates as it progresses.

“Any further witness appeals will be issued in due course. Any speculation is extremely unhelpful at this time."

Video Loading Video Unavailable Click to play Tap to play The video will start in 8 Cancel Play now

(Image: PA)

(Image: PA)

The men behind the London Bridge and Westminster terror attacks were known to police - but nothing had yet been revealed about today's suspect or suspects when Trump tweeted.

Prime Minister Theresa May said: "I never think it’s helpful for anyone to speculate on what is an ongoing investigation.

"The police and security services are working to discover the full circumstances of this cowardly attack and to identify those responsible."

Neil Coyle, the Labour MP who has London Bridge in his constituency, lashed out at the US President's response.

He said: "Instead of slagging off a major ally's police and security service network, Trump should perhaps focus on his own backyard. He was reluctant to criticise Nazi-flag waving extremists at home."

He added: "Scotland Yard makes an arrest every four days using counter-terrorism intelligence. The police need more resources but definitely don't need Trump's idiotic excuse for extending his travel ban."

Video Loading Video Unavailable Click to play Tap to play The video will start in 8 Cancel Play now

A former chief advisor to Theresa May, Nick Timothy, added: "True or not - and I'm sure he doesn't know - this is so unhelpful from leader of our ally and intelligence partner."

Police say a suspected "improvised explosive device" today injured 22 people, mostly with flash burns, on a packed rush hour train in Parsons Green, west London.

Theresa May was returning to Downing Street this morning from her Maidenhead constituency to lead a meeting of the Cobra emergency committee at around 1pm. She and Labour leader Jeremy Corbyn paid tribute to emergency workers.

Trump has repeatedly clashed with Sadiq Khan, London's first Muslim mayor, over his response to terror in the past.

Today Mr Khan dismissed the US President's comment, telling LBC: "I've simply been too busy this morning to look at my Twitter. I'm absolutely not going to go there. My priority is making sure we do all we can to keep Londoners safe. Our priority today is catching the individual or individuals responsible."

Mr Khan "utterly condemned" what he called "hideous" terrorists who want to "harm us and destroy our way of life."

Video Loading Video Unavailable Click to play Tap to play The video will start in 8 Cancel Play now

(Image: AFP)

(Image: carefreealex/Instagram)

London's mayor added: "As London has proven again and again, we will never be intimidated or defeated by terrorism."

Trump also used today's attack to try and justify his travel ban on people from Muslim nations to the US.

Even though the number, identity, religion or nationality of any terrorists has not been revealed, he wrote: "Loser terrorists must be dealt with in a much tougher manner.

"The internet is their main recruitment tool which we must cut off & use better!

(Image: Splash News)

"The travel ban into the United States should be far larger, tougher and more specific-but stupidly, that would not be politically correct!

"We have made more progress in the last nine months against ISIS than the Obama Administration has made in 8 years.Must be proactive & nasty!"

Donald Trump later insisted he WAS briefed on the Parsons Green attack.

Video Loading Video Unavailable Click to play Tap to play The video will start in 8 Cancel Play now

(Image: AFP)

It comes after Theresa May dismissed his claim the culprit had been "in the sights of Scotland Yard” before the bomb as “speculation”.

Speaking as he met an 11-year-old mowing the White House Lawn, the US President said: "It’s a terrible thing. Just keeps going and going and we have to be very smart, we have to be very very tough. Perhaps we’re not nearly tough enough.

"It’s just an absolutely terrible thing - in fact, I’m gonna to call the Prime Minister right now."

Asked if he’d been briefed on any intelligence about Parsons Green, he said: “Yes I have, on numerous things happening, including North Korea.”

The Wall Street Journal today reported that Britain noted a risk to crowded public spaces one day before the attack.

Lib Dem MP Ed Davey said: "This intervention is not only highly insensitive but could hamper the work of our security services.

"It is insulting to the victims of this attack that Donald Trump is already using it to try and further his divisive political agenda.

"Once again, Trump has shown he is not fit for the office of US President."