A train was delayed for about three hours with passengers stuck on board after vandals placed traffic cones on tracks in south-west London.
Fifteen cones were placed on the line, used by the London Waterloo to Reading service, near Mortlake Station at about 23:10 BST, South West Trains said.
The train was damaged and the service was halted at Mortlake Station, where passengers were able to get off.
The train firm has apologised to passengers for the delay.
A spokesman for the South West Trains-Network Rail Alliance said: "Passengers on the 10.50pm London Waterloo to Reading service were delayed by around three hours last night after vandals placed around 15 traffic cones on the line, damaging the train.
"Fitters worked on the damaged train and were able to get it moving at low speed into Mortlake Station where passengers got off.
"We are extremely angry at the impact such irresponsible actions by vandals has had on our customers and we would urge anyone with information about the incident to contact British Transport Police."
The train firm said it provided taxis for passengers and an extra train was arranged.
Julian Brookman, who was a passenger stuck on the train, told BBC London it usually takes him 20 minutes to get from Mortlake to Twickenham.
But after the delay he and some other passengers shared a taxi to get home after the train returned to Mortlake.