A woman was bitten by a dog in a Chesterfield park as she tried to protect her own pet.
The woman was walking through Holmebrook Valley Park, near Chesterfield, with her two dogs when another dog, thought to be a red Staffordshire bull terrier that was not on a lead, ran up to them and started to attack one of them.
As the woman tried to force the dogs apart she was bitten on her hand.
The incident happened at about 9.15am on Wednesday, December 7.
It is believed the dog responsible for the attack was with a man who was also walking a white Staffordshire bull terrier, which was on its lead.
The man was white, around 5ft 8ins tall, of a medium build and in his late 50s or early 60s.
He was wearing a dark grey flat cap and long black winter coat and is believed to have spoken with an accent, possibly Italian or Spanish.
Anyone with information should call PC Julian Matthews at Derbyshire Police on 101.