A man was assaulted in Wakefield after approaching a group of teenagers who had been causing a disturbance.
The 51-year-old victim suffered serious facial injuries when he was attacked by one of the teenagers in Green Lane, Alverthorpe, at around 8pm on Friday, August 18.
Now detectives are appealing for the public's help in identifying the teenager responsible.
The attacker was described as being white, aged between 16 and 18, just over 5ft 9in and slim. His light blond hair was styled longer on top and swept over to the right and was shorter at the back and sides.
He was wearing a light blue T-shirt and dark blue jeans.
Anyone with any information is asked to call Wakefield District CID via 101, quoting crime reference 13170381719.