(The Associated Press distributed the following on October 19.)
LONDON — A London subway train derailed Sunday for the second time in less than 48 hours, injuring seven people and forcing the closure of a busy station.
Mayor Ken Livingstone said the derailments raised “grave questions” about subway safety, and a rail union threatened strikes unless authorities reversed a decision putting private companies in charge of track maintenance.
The sixth and final carriage of a Northern Line train derailed Sunday morning as the engine entered Camden Town station, London Underground spokesman Stuart Ross said. Another spokesman said the accident likely was caused by track problems.
The station, which attracts thousands of Sunday shoppers headed for the popular Camden Lock flea market, was closed after the derailment, and London Underground said it was unlikely to open before Monday morning.
The nearby Royal Free Hospital said it treated seven wounded, including a man with a broken leg and another with head injuries. The other five had minor injuries.
London Underground said 213 passengers were evacuated from two trains behind the one that derailed, which carried about 70 people.
All the injured were in the final car, which derailed in the tunnel about 100 feet before the station, said Darren Dovey, assistant divisional officer of the London Fire Brigade.
The train was traveling at a “relatively low speed” when one of the six carriages struck a wall, Ross said.
Mike Strzelecki, London Underground’s director of safety, said it appeared track problems likely caused the derailment.
On Friday evening, a Piccadilly Line train derailed at low speed at Hammersmith Station in west London. No one was injured in the incident, which London Underground said was likely caused by a cracked rail.
A derailment at Chancery Lane station in January injured 32 people and forced the Central Line to close for three months. A report said the accident occurred after a motor fell from the train.
Livingstone said there would be an investigation into the derailments, which raised “grave questions about the safety of the system.”
A spokeswoman for Tube Lines, the private consortium responsible for maintaining the Northern Line, said it was investigating when the track was last checked.
Bob Crow, leader of Britain’s biggest rail union — the Rail Maritime and Transport Union, threatened strikes unless authorities suspended maintenance contracts given earlier this year to private companies.