The attack happened on a pathway near Buckingham Road, Bletchley
A man has been arrested on suspicion of sexually assaulting an 82-year-old woman.
The woman was assaulted as she walked on a pathway near Buckingham Road in Bletchley, Buckinghamshire, at about 13:00 BST on Friday.
A man pushed her to the ground and attacked her before walking off, police said.
A 20-year-old man from Bletchley had been arrested and is being held in police custody.
Samantha Arnold, from Thames Valley Police, said: "I would still like to speak with a man who was seen picking fruit around the time of the sexual assault. He has been described as a white man in his sixties and wearing a cream jacket or top. He was travelling on a push bike.
"I believe this man might be a witness and therefore could help our investigation."
