
Hundreds of armed police in speedboats zoomed down the river Thames today as part of major anti-terrorist drill in London.

Specialist officers clad in black uniforms and toting machine guns stormed a hijacked cruise boat to rescue hostages from six 'terrorists' in the east of the capital.

The London Ambulance Service, London Fire Brigade and the RNLI were also involved in the exercise on the country's busiest waterway.

Terror drill: Hundreds of armed police in boats zoomed down the river Thames today as part of major anti-terrorist drill in London

Help is on the way: The police raced to the cruise ship to help to rescue the hostages who were pretending to be trapped in the boat

Begging for rescue: Actors pretending to be hostages pressed their hands up against the windows of the cruise ship

Hostage situation: An actor pretending to be a terrorist held a firearm to the head of an actor pretending to be a hostage

Some 200 armed officers were seen racing down the river towards the ship which was heading along the Thames estury towards central London.

They approached the cruise ship as cowering civilians banged on the windows pretending to be desperate for help.

One of the scenarios played out involved the 'terrorists' throwing a pretend corpse overboard and the police collecting it from the water.

Officers then boarded the ship and after a pretend gunfight 'secured' the terrorists before attending to the hostages they had rescued.

Police chiefs were quick to emphasise the first live excersise of its kind was not in anticipation of any specific attack but just general training to remain 'match fit' for combating terror.

Scotland Yard Commander BJ Harrington, in charge of the Thames exercise, said: 'We've seen attacks across the world, with tragic circumstances and in different guises. What we do is test and exercise all the time.

'This is just a natural progression into what is a busy waterway through the centre of the capital, to make sure that there is a good police response that works well in a marine environment.'

One of the scenarios played out involved the 'terrorists' throwing a pretend corpse overboard and the police collecting it from the water

Commander BJ Harrington, head of the Met's Public Order Command, added: 'It's important to point out that the exercise has not been designed in response to any specific threat. There's no information that we have that we're preparing for.

'Of course, we have seen a number of incidents abroad in the past few years: Nice, Berlin - we have seen different methodologies developing, and, of course, the river runs right the way through London so why wouldn't we prepare for that.'

The exercise comes just two weeks after the Met's most senior counter-terrorism officer, assistant commissioner Mark Rowley, revealed that security services have thwarted 13 potential terrorist attacks in the UK in less than four years.

The figure is one higher than the last tally given in October.

Assistant commissioner Rowley said up to 500 counter-terror investigations are operational at any one time, with investigators making arrests at a rate of close to one a day on average since 2014.

The London Ambulance Service, London Fire Brigade and the RNLI were also involved in the exercise on the country's busiest waterway

Man down: Police pretended to shoot at a terrorist who pretended to fire a machine gun in their direction from the boat

The official threat level for international terrorism in the UK has stood at severe - meaning an attack is 'highly likely' - for more than two years.

Commander Harrington said the exercise marks the first time all the involved agencies have come together to test their interoperability and effectiveness as a group, and hoped it would act as a deterrent to any would-be attackers.

He said: 'Most importantly, we give the people who are going to have to do this tricky and difficult and dangerous stuff the opportunity to have confidence that they can do it, and hopefully, above all, give confidence to people who live and work and visit London to say the police, the agencies, blue light agencies and other public service agencies, are in a really good position to protect them and keep them safe.

Drama: The hostages were seen begging the police to rescue them as officers tried to create a very realistic drill

Secured: Officers then boarded the ship and 'secured' the terrorists before attending to the hostages they had rescued

'I do hope there is a deterrent effect in this when they see how effective our people are.'

A previous major inter-agency exercise in June 2015, Operation Strong Tower, saw hundreds of officers respond to a simulated terror threat in a disused London Underground station.

This was just five days after 30 Britons were killed when a gunman attacked holidaymakers on a beach in Tunisia.

Sunday's operation, code-named Anchor, comes just 24 hours after French police shot dead a 39-year-old gunman at Paris's Orly airport.

Two hundred police officers stormed a hijacked cruise boat to rescue hostages

Warning: The Met police put out a warning tweet so that people would know there was no danger

On guard: Three officers stood vigilant at the back of the boat, holding their guns to their shoulders as their colleagues rescued the hostages

Speaking from the scene of the exercise, Commander Harrington praised the bravery of service personnel who deal with terrorist situations.

He said: 'I just want to stress the bravery of the people involved in this. They go forward to face what is a deadly attack - they have no concern for their own lives.

'They're potentially heavily armed and add to that the complexity of a tidal river and I think we should have all praise to them. It fills me with confidence that these people are prepared to do this kind of thing.'

In the shooting at Paris' Orly airport yesterday, a convicted criminal with links to radical Islam shouted 'I am here to die for Allah, there will be deaths' seconds before he was shot dead during the attack.

The 39-year-old, named locally as career criminal Ziyed Ben Belgacem, was killed after wrestling a soldier's gun from her and fleeing into a McDonald's.

He sent a text message to his brother and father stating 'I shot the police', shortly before he was killed.

Boats race to the ship to take on six pretend terrorists who had taken hostages and were driving towards central London

Rescued: Hostages were saved by the police officers who climbed aboard the ship from their black speed boats

Revealing his chilling final words, Paris prosecutor Francois Molins said an anti-terrorist enquiry had been launched.

Today's exercise also comes after it was revealed that Britain's security services were probing at least four plots to commit terrorist atrocities, with shopping centres and stadiums thought to be at particular risk.

In February Max Hill QC, the independent reviewer of terrorism laws, said Britain faced a terror threat not seen since the IRA bombings of the 1970s, and Islamist extremists were targeting UK cities.

He revealed his 'enormous concern' over the threat posed by British jihadis returning from Syria fighting for Islamic State.

Last July a gunman in Munich murdered nine people during a mall shooting spree.