They pulled WPC Katie Hicks from the wreckage of her squad car after two Green Goddess crews were unable to swiftly cope with the smash, which killed driver PC Christian, 29.

He took the brunt of the impact when their Vauxhall Astra marked car, answering a 999 call, swerved off the road and slammed into a tree in Tottenham, North London. Police drove to the local fire station for help as 21-year-old Katie's fiance was alerted over the radio.

He helped to pull her out. She was critically ill in hospital last night.

Fire Brigades Union London Regional official Matt Wrack said: "This tragic accident highlights the nonsense of the Government's claim that the Army are coping.

"They are not equipped to deal with a variety of different situations, particularly accidents such as this.

"The Army sent two Green Goddesses and breathing apparatus - but that would have been little use in this type of road traffic accident."

Other strikers across Britain suspended their stoppage to save lives.

In Wembley, North London, firefighters plucked two people from cars after a collision. An onlooker said they arrived about 15 minutes before two Army teams in Green Goddesses.

Also in North London, FBU members were summoned to a death crash scene by police because Green Goddess crews "couldn't cope." Soldiers had tried in vain to cut a woman from the wreckage of a red Alfa Romeo after it came off the road and crashed into a tree on Hampstead Heath.

The 25-year-old woman had been trapped for hours next to the body of a man aged 29 when a fire engine arrived from Kentish Town fire station.

Striking firefighter Richard Magnus said: "Police officers pulled up at around 7.30am, or 7.45am, asking us to help out in a fatal road accident.

"I spoke to the officer, who said 'The Army are having great difficulties coping' and asked us to help.

"We mobilised one fire engine and were there in about 45 minutes. The Army personnel looked very relieved to see us.

"The man was already dead, they were trying to cut the woman, who was still conscious, out of the car, but were not getting very far.

"We turned up and took over. It took about 30 minutes to cut her out." Mr Magnus added: "It is difficult for us, because obviously it makes the strike less effective to be responding to calls.

"But if lives are at risk we have no hesitation in attending when we are asked to."

The woman was in a critical condition in hospital last night.

Army spokesman for London, Colonel Peter Dick-Peter, admitted that Green Goddess crews were less capable of dealing with road accidents than regular fire crews.

He said: "Our soldiers were in the process of cutting the casaulties from the car when the London Fire Brigade arrived and offered to assist.

"Their equipment is more sophisticated than ours, so we gladly accepted.

"We are not in the business of competing with the Fire Brigade, there is no question that they have better capabilities in situations like this. We are in the business of saving lives. It is not a competition and it does not matter who does it, as long as it is done."

In Scotland a firefighter told how he and his colleagues left their picket line in an attempt to save two elderly people who died after their car plunged into a harbour.

Bill Foster, 37, was at Kirkcaldy fire station in Fife when an ambulance on its way to the incident asked the firefighters for help.

Mr Foster and five colleagues jumped into a fire appliance and joined the rescue effort at Pettycur Bay Harbour in Kinghorn.

With the help of an RNLI lifeboat from Kinghorn, they battled in vain to save the couple.

Mr Foster said: "We were on the picket line on night shift when this ambulance on a blue light came tearing up to us and asked us for help.

"We wouldn't have got there any quicker if we hadn't been on strike.Our only thoughts were to save the lives of these two people.

"Whether we're on strike or not we'll always leave the picket line to save lives."

A woman in her thirties died in a fire in Co Down, Northern Ireland. Her body was found by striking firefighters at her flat at Ballynoe Gardens in the Kilcooley Gardens area of Bangor.

Strikers also left their picket lines to help a trapped motorist in Northumberland.

They responded after a member of the public, who had spotted a road accident, raced to the fire station and reported the elderly driver was trapped.

They used cutting gear to free the driver and RAF personnel, who arrived on the scene minutes later, watched as the firefighters completed the rescue, which took more than 30 minutes.

Sub-officer John Buller, one of the strikers involved, said: "We were happy to respond to the incident because the guy who came to the fire station was panic-stricken and firefighters have a moral obligation to act if life is thought to be at risk."

In Okehampton, Devon, a 14-year-old girl was being questioned about hoax calls made to the fire service.

A woman supporter of the strike caused firemen to break their picket line when she crashed her car while waving to them.

The woman beeped her horn and waved as she was passing their HQ in Edinburgh , only to collide with the car in front.