A 17-year-old girl has been attacked and sexually assaulted in Milton Keynes.
The attack happened as she walked home past the Milton Keynes Bowl at about 2200 BST on Wednesday.
The girl was pushed into bushes and subjected to a serious sexual assault before screaming and fighting off her attacker, who fled.
A 29-year-old man has been arrested and is in custody, but Thames Valley Police are appealing for witnesses.
Officers want to hear from anyone who was in the area at the time.
Det Insp Kelly Glister said: "This was a serious and frightening incident in which a teenage girl was attacked by a complete stranger."
The man is described as 6ft tall, slim, with sideburns and aged between 21 and 30.
He wore dirty white trainers, light blue slim-fit jeans and a white top.
He may also have been riding a green or turquoise bike, which had writing on the frame, around the area at the time.