A 14-year-old girl was bitten by a dog in Olden Road, Rectory Farm, Northampton.
The girl had approached the dog which was tied up to a railing outside a shop and attempted to stroke it, at which point it bit her on the left arm and leg.
The owner came out of the shop and ran away with the dog.
The teenager required hospital treatment as a result of the bites caused by the attack, which took place at about 1.10pm on Tuesday 12 August .
The dog was a light grey and white Akita or Huskey. The owner was a white man, in his mid-20s, 5ft 8in, with a thin build and pale complexion. He had shoulder- length brown hair and was wearing a hooded top and jeans.
Police would like to speak to anyone who may have witnessed this incident or have any information regarding it.
Witnesses or anyone with information is asked to call police on 101 or Crimestoppers anonymously on 0800 555 111.