The Potters Bar rail disaster claimed its seventh victim this evening when emergency services said a passenger rescued from the scene had died in hospital.
Police confirmed tonight that a seventh person had died in hospital of injuries sustained in the crash.
The train was travelling from London to King's Lynn in Norfolk, East Anglia, when it derailed near Potters Bar and smashed into the commuter railway station.
"Five people died at the scene and a sixth died in hospital," a spokeswoman for Hertfordshire ambulance services said.
A spokesman for the three north London hospitals that were taking in the injured passengers said a total of 26 people had so far been brought in for treatment, suffering head and chest injuries, fractures, cuts and abrasions.
Although many were "walking wounded", several were undergoing emergency surgery and at least two were in a serious condition, the spokesman said.
Police said the force of the accident was so great that the rear of the four-carriage train careered into the station.
One eyewitness said she saw a woman trapped under a railway bridge, which appeared to have collapsed.
Emergency crews had to dig her out of the debris.
"I saw two injured people walking away," the witness told Reuters. "One man had head wounds. The train is tipped slightly with its wheels in the air."
It was the latest tragedy to hit the trains in Britain, where the world's first public steam railway began, in 1825.
In recent years the network has been hit by a string of disasters, leading to long delays for commuters and fears of Third-World safety standards in one of the world's richest countries.
Workers battled for 30 minutes to free one woman from under the wheels of a carriage tipped on its side. The walking wounded staggered into a local supermarket-turned-first aid station.
The derailment was less than five miles from Hatfield, where an express came off the tracks in October 2000, killing four people.
In February last year, 10 people were killed and dozens injured when a passenger express collided with a crashed car before being hit by a freight train travelling in the opposite direction, near the Yorkshire town of Selby in northern England.
In October 1999, two trains collided near London's Paddington station, killing 31 people. One of the trains had gone through a red signal.
Nicholas Anastasiou, who owns a shop beside the station, told Sky News: "All I can see is one carriage, I think it's the last carriage, laying across the track, people everywhere, loads of people on the platform running away from the scene, blood pouring everywhere. Terrible.
"All I heard was a big bang, and as I went out of the shop I could see people running around everywhere and I saw the train hanging off ... and half the bridge on the road, cars smashed everywhere."
A spokesman for operators WAGN said the train was a service from King's Cross, London to King's Lynn, Norfolk.
Shares of National Express, which owns WAGN, fell six per cent after the accident, which comes eight months after the government forced network operator Railtrack Plc into insolvency.
The end of Railtrack came amid spiralling costs, a deteriorating service and passengers' confidence evaporating after a string of crashes. Its handling has left question marks over the fate of Transport Secretary Stephen Byers, also under pressure for a political wrangle involving his media staff.