Thames Valley Police has commenced a criminal investigation after a reported assault in Banbury left a man with serious head injuries.
The attack occurred in Parsons Street during the early hours of Sunday, July 19.
A man aged in his twenties received a punch to the head and needed hospital treatment.
He has since left hospital.
Detectives have published an image of a man they believe could hold relevant information about what transpired.
The force has indicated that appeals of this nature are intended to locate individuals who may possess pertinent details, not to suggest any form of culpability.
Two additional people who were observed in the vicinity have been identified as potentially valuable sources of information.
A woman and a man were seen together at the scene and departed in company.
The woman is described as being in her twenties or thirties, of slender build, and standing approximately 5ft 3in to 5ft 4in tall.
She had brown hair reaching her shoulders, styled partially up.
Her attire comprised a midi-length dress in black or navy, heeled footwear in a brown tone, a bag worn across the body, and a jacket in a dark shade.
The male witness is believed to be aged between 20 and 39, of slight physique, and measuring roughly 5ft 8in to 5ft 9in in height.
He had short brown hair.
At the time, he was dressed in a short-sleeved top in black, either a polo shirt or a plain t-shirt bearing a small chest emblem, casual trousers in a cream or tan shade resembling chinos, and brown leather shoes.
Anyone who can identify the individual shown in the released photograph, or who possesses any information regarding the assault, should contact Thames Valley Police quoting reference 43260369310.
Alternative contact methods include the 101 telephone number or the force’s online reporting facility.
Those wishing to provide information anonymously may do so through the independent charity Crime Stoppers.