Seven people have died after the 12.45pm Kings Cross to Kings Lynn West Anglia Great Northern passenger train crashed at Potters Bar railway station at around 12.55pm.
Three more casualties have life-threatening injuries while nine are in a serious condition, according to the ambulance service, and there are 25 to 50 walking wounded.
There are also reports that people are trapped inside a carriage which is on its side across four lines, and that a road bridge has collapsed.
One of the carriages mounted the platform and is wedged under the station's roof, according to reports.
Eye-witnesses have described the scene as 'terrible', saying parts of the train were in the car park and that one carriage is lying across the platform.
An additional eyewitness said it appeared the train had become derailed after crossing a road bridge close to the station and debris from the bridge had fallen onto Darkes Lane, one of the main roads in the town.
Reports say at least one passenger has been hit by failing debris from the bridge and that others are still trapped in the wreckage.
The train driver, Andy Gibson, from London, was unhurt. Mick Rix, rail union Aslef's general secretary, said: "This is a terrible tragedy, first of all for those involved in the crash and the families of those who may be bereaved or injured, but also for the railway industry as a whole.
"We send our deepest sympathies to all concerned, but we also want to express our pride in the prompt and efficient action of driver Andy Gibson, who we understand rendered vital assistance to passengers on the train."
Bedfordshire and Hertfordshire Ambulance service have said the latest casualty figures indicate three fatalities, three people with life threatening injuries, nine serious injuries, and between 25 and 30 walking wounded.
Mark Purcell, spokesman for Barnet Hospital said: "We have been told to expect quite a number of people from the scene, some of them critically injured.
"The A and E department has been cleared. Doctors and nurses from the hospital have gone to the scene, which is about a mile away.
"What normally happens is that people are treated at the scene. We've been told it may well be burns, but we are expecting a whole range of injuries," he added.
Eyewitnesses said the final carriage had hit the railway station platform, with reports that part of the train had hit a bridge.
Adam Anderson, said: "The side of the train is stuck under the station roof and the bridge is damaged. Our whole station is trashed. The bridge is gone. I was talking to one police officer who said there was an old lady under the bridge."
Another eyewitness, Andy Perversi said: "I was waiting for the train to come in and I turned around and the train was on the platform. Everyone turned round and started to run away. I was just eating my lunch and I heard a noise and saw the train.
"I was trying to help people off the train with people being stretchered off." he added.
The station platform is completely wrecked and one of the carriages is on its side trapped underneath the station roof and one of the building is demolished.
Barnet and Potters Bar Times photographer John Macdonald-Fulton has said he saw four people being stretchered away from the scene but it unclear if they were alive.
The Sainsbury's store in Darkes Lane is being used as a first aid post. A member of staff said: "Our first aiders were first on the scene. Someone came rushing in and told us what had happened and anyone who knew what to do went rushing over.
"You can see the train from the store and we've got wounded people in the store now," she added.
The derailment is close to Hatfield, where a GNER express came off the tracks in October 2000 in an accident which claimed four lives.
An emergency number has been issued for those concerned about relatives or friends. The number is 0845 944 1551.
May 11, 2002 02:34
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