A fight in a Tring town centre pub on Sunday evening saw a man struck in the face with a glass or bottle.
The incident took place in the Black Horse Public House, on Frogmore Street, at 10.30pm
A 27-year-old man suffered cuts and bruising to his face.
The offender is described as a white man, 6ft 2ins tall, of medium build with short spikey style blonde/brown hair, wearing a Tring Athletic football shirt.
PC Christopher Hulian is investigating. He said: “It is highly unusual for an incident of this nature to take place in Tring.
“I am appealing for witnesses to this assault to come forward, specifically those involved in stopping the fight.”