The Potters Bar rail crash occurred on May 10, 2002 at Potters Bar, north of London, when a northbound train derailed at high speed, killing seven and seriously injuring another eleven.

A West Anglia Great Northern train service left King's Cross station at 12:45 bound for King's Lynn in Norfolk. Travelling at around 100mph, it crossed over a set of points just before Potters Bar railway station at 12:55. As the final coach travelled over the points it derailed, spinning around 90 degrees. The momentum carried the carriage into the station, where it mounted the platforms at right angles, before coming to rest under the platform canopy. During this, one end of the carriage struck a bridge parapet, sending debris onto the road below.

Six of the victims were travelling on board the train, while a seventh was killed by the falling debris.

A Health and Safety Executive report released in May 2003 found that the points were poorly maintained, and this was the principal cause of the accident. The bolts that held the stretch bars that keep the rails apart had become loose or missing, resulting in the points moving while the train passed over them. The points had been fully inspected on May 1 by a team working for the private railway maintenance firm Jarvis , and there had been a further visual inspection on May 9, the day before the crash, with no problems reported.

Initially after the accident, Jarvis claimed that the points' poor condition was due to sabotage of some sort, and that its maintenance was not to blame. However, no solid evidence of any sabotage has ever come to light. Furthermore, the HSE report found that other sets of points in the Potters Bar area showed similar (but not as serious) maintenance deficiencies, and the poor state of maintenance "probably arose from a failure to understand fully the design and safety requirements".

The tragedy sparked a debate about whether private maintenance firms were paying too little attention to training and safety. In 2003 Network Rail announced it was taking all track maintenance in-house, ending the use of private contractors except for large-scale renewal or development projects.

On April 28 2004 Jarvis sent a letter to the victim's families admitting liability for the accident. The company said that it would formally accept "legally justified claims" after making a financial provision of £3m.

In the letter Kevin Hyde, chief executive, wrote: "In the aftermath of the crash, when Jarvis was under great pressure to explain itself, we were drawn into a debate about the possible causes of the crash. On behalf of the company and my colleagues, I would like to apologise for the hurt and anger our actions in responding caused."

The writer Nina Bawden was badly injured in the crash, and her husband was killed.

List of the deceased

• Austen Kark, 75
• Emma Knights, 29
• Chia-hsin Lin, 29
• Alexander Ogonwusi, 42
• Agnes Quinlivan, 80
• Jonael Schickler, 25
• Chia-Ching Wu, 30

See also

• List of British rail accidents

External links

• Guardian Unlimited Special Report
• BBC News In Depth - Potters Bar Crash