It is thought the bus driver was the only person on board at the time (picture taken by James Capel)
The driver of a double-decker bus which had its roof ripped off when he drove it under a railway bridge has been arrested on suspicion of drink-driving.
The 49-year-old man failed a breath test at the scene after he drove under the bridge in Langley, Slough.
The incident led to rail delays of up to 60 minutes between London Paddington and Reading before services resumed just before 2000 BST.
The driver was the only person on board and was not injured.
Police said there was no structural damage to the bridge and the road was reopened after several hours.
Jenny Mulholland, landlady of the nearby Willow Tree pub, said: "I just happened to look out the window and saw a bus with no roof and thought, 'that's a sight you don't see very often'."
Engineers worked at the scene to restore normal rail services.