Tube repair company admits it may be responsible for yesterday's derailing accident on the Central Line

The Metronet-maintained Central Line remained partially closed today following the derailment of a train yesterday between Mile End and Bethnal Green London Underground stations.

Metronet, the PPP company, is investigating the cause of the incident, which resulted in 15 passengers being taken to hospital, but thinks that it was caused by something falling on the track.

A Metronet spokesperson said: 鈥淲hilst it is important not to pre-judge the outcome of the investigation, our initial reports suggest that a bale of material became dislodged from its licensed storage position in a tunnel cross-passage.鈥�

Metronet apologised to passengers and ordered an audit of all storage sites used by its staff and contractors.

The derailment is the second on the Central Line in four years. In 2003 a train derailed at Chancery Lane, three months after Metronet assumed responsibility for it.