(Adds details and quotes) LONDON, July 5 (Reuters) - An underground train came off the rails in London on Thursday, stranding hundreds of passengers, but police called it a minor incident and said there was no terrorist link. They said one person was slightly injured and that a large amount of dust had been displaced in the tunnel, but otherwise the damage was limited. "It was a relatively minor derailment," police superintendent Phil Trendell told reporters at the scene. "There's nothing to suggest a terrorist link. "I'm pleased to say there are no serious injuries." The train came off the rails at 9:05 a.m. (0805 GMT), shortly after the rush hour, in the east of the city. The London Underground transport system said it was investigating whether there had been an obstruction on the track. Hundreds of people from the derailed train and another that was caught in the tunnel behind it had to be evacuated, an operation that rescue workers said had gone smoothly.