Rail services through Gatwick Airport are being disrupted after a train hit an obstruction on the tracks.
Rail operators Thameslink and Southern first reported the issue at about 06:00 GMT on Tuesday, saying that an obstruction had been struck by a train near Salfords station, in Surrey.
The train companies say trains running to, from or through Gatwick Airport may be cancelled, delayed by up to 30 minutes or revised and services that are running may use alternative platforms at some stations.
A spokesperson said a train had correctly gone through a signal and hit the object, knocking the train’s shoe gears off – which help the train get power from the electric third rail.