A man was seen exposing himself and committing an indecent act in a Dewsbury street before leaving in a white Transit style van.
Dewsbury Police would like to speak to anyone who has information about the incident which took place between 3.50pm and 4.20pm on Friday August 28 outside a retailers on Railway Street, Dewsbury.
He was described as white, 5ft 8ins tall and stocky with a shaved head. The man was wearing grey trousers, black boots and a blue polo shirt with some orange around the collar.
Anyone who has information should contact PC 6816 Charlotte Armitage at Dewsbury Police on 101.
Information can also be given anonymously to the independent Crimestoppers charity on 0800 555 111.