Detectives investigating a sexual assault on an 83-year-old woman in Heckmondwike are looking for a 15-year-old boy.
The victim was walking her dog along the Spen Valley Greenway between Beck Lane and Station Lane when she passed three teenagers.
One of the boys made crude comments towards her before smacking the pensioner on her behind.
The victim continued on her way and, as she walked along Beck Lane on her way home, saw the same three teenagers. Again, one of the boys made crude comments towards the victim.
The suspect was white, around 15-years-old and 5ft 6ins tall. He had short brown hair, wore large full framed dark glasses, a white T-shirt and a navy jacket.
The other two suspects were described as being 15-year-old boys.
Inquiries are ongoing and any witnesses to the incident at around 6.45pm on Wednesday are being asked to contact Detective Constable Rob Rutherford at Dewsbury CID via 101.
In particular, police are appealing for a man in his 50s who was cycling along the Greenway at the time of the first incident, to contact them.