Armoured vehicles have been brought in to clear the streets of London for the first time by police to tackle what senior officers say is the worst rioting and looting in living memory.

More than 6,000 officers – including 2,500 mostly public order-trained officers and 3,500 local officers – were on duty as violence spread from north, to east, west and south London on Monday night. Fires burned in Croydon, Clapham Junction and Hackney and there were disturbances outside the capital in Liverpool, Birmingham and Bristol.

Senior officers say the violence and looting on Monday night was the worst in living memory; eclipsing the 1980s inner city riots in Toxteth, Brixton and Tottenham at the height of Margaret Thatcher's premiership.

Armoured vehicles – known as Jankels – were brought in during the early hours of Tuesday morning in Clapham Junction where much of the worst looting and arson took place. The vehicles were driven on to Lavender Hill to push back a crowd of 150 looters who had smashed up Debenhams and other stores and businesses in the area. Jankels were also out in Hackney.

Their deployment brought echoes of Northern Ireland during the Troubles to the streets of the capital and marked the start of what sources say are much tougher tactics against rioters. But a police source said the use of water cannon was a decision for government, not Scotland Yard.

The use of armoured vehicles to clear rioters after hours in which it appeared the police had lost control of the streets means they will be used again if violence continues, the Yard said.

Across London, officers were fully stretched and members of the public were injured as bottles, petrol bombs and other missiles flew.

One man in his 60s received life-threatening head injuries, while three people were arrested on suspicion of attempted murder after a police officer was knocked down by a car in Brent, north-west London.

The Met received more than 20,000 999 calls, four times the normal number.

All police cells in London are full and anyone arrested now is being taken to surrounding areas, Scotland Yard said.

A spokesman said: "A significant number of arrests were made overnight, leading to all our cells being full and prisoners being taken to surrounding forces."

London's ambulance service said it took 22 people to hospital from the main areas of the disturbances, although others were treated at the scene or made their own way to accident and emergency departments across the capital.

The capital's fire brigade said it experienced its busiest night in recent history, tackling fires across the capital including huge blazes in Enfield, Croydon and Clapham Junction.

It answered 2,169 999 calls between 6pm on Monday and just after 7am on Tuesday, around 15 times the average.

Police faced severe criticism as it appeared they had lost control in some areas on Monday night. But faced with criticism that not enough officers were on the streets, the Met defended its operation, saying there were 2,500 public order officers in addition to 3,500 officers in boroughs who were on duty.

The Yard brought in help from 12 other police forces and said it will do so again on Tuesday.

"Officers and staff continue to work long hours at short notice in very challenging circumstances," Scotland Yard said. "We continue to have the plans and resources in place to respond to any further disorder, deal with normal policing across the city and keep Londoners safe."

The acting Met commissioner, Tim Godwin, has called for all special constables to report for duty and asks employers to support his request.

Around 13 000 officers will be on duty over the next 24 hours, the Met said.

PC Paul Deller told BBC Radio 4 that the officers gave it everything. Asked whether there were enough police on the ground he said: "Probably there aren't but we gave it everything we could."

More than 200 people were arrested, bringing the total number of arrests over the last three days of disturbances to 450. Sixty-nine people have been charged and officers from homicide and serious crime command worked through the night to examine CCTV images. Those arrested are being taken to police stations outside the capital because cells in London are full.

Scotland Yard said "disturbing" levels of violence were directed at police again on Monday night. Forty-four officers were injured, including one who will need surgery after being hit in the eye.

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