THE RAIB is investigating a reported near-collision between a London Underground train and a National Rail service on Sunday night.

An image from the scene shows a Chiltern Railways unit and a train of Metropolitan Line S-Stock at a stand  just a few metres apart at Chalfont & Latimer, the junction for the Chesham branch.

Reports have claimed that the Chiltern train took the wrong route at a crossover, taking it towards the Metropolitan unit, and other unconfirmed reports say that the points and track were damaged. 

Transport for London said: ‘We apologise to customers disrupted by the closure of the Metropolitan line between Chalfont & Latimer and Chesham. This is the result of an incident involving a Chiltern Railways train near Chalfont & Latimer station. We are working with Chiltern Railways to determine exactly what happened, and our engineers will repair the railway to return it to service as quickly as possible.’

The Transport for London website was still reporting no service on the Chesham branch on Tuesday afternoon, and attributing the suspension to a ‘track fault’.

Chiltern Railways said: ‘We have an excellent safety record and are working with the Rail Accident Investigation Branch to understand the causes of this incident.’