A section of the London Tube network has been closed after builders drilled a hole through the roof of an underground tunnel, causing lumps of concrete to fall on to the track.
Central Line services have been suspended between Marble Arch and White City after the masonry fell on the track in the Shepherd’s Bush area while services were running.
No trains or any part of the track was damaged from the incident.
A spokesman for TfL told The Independent the delays were expected to last “a couple of hours” while workers tried to establish how the hole was created.
The contractors are believed to be working on an extension to the Westfield shopping centre.
Operations Director, Peter McNaught, said: "I apologise to customers affected by delays on the Central line this evening, this is due to an obstruction on the track in the Shepherds Bush area. We are working hard to resolve the problem as soon as possible."