Police are appealing for witnesses following an assault outside McDonalds restaurant in Queensway, Leamington, between 12am and 12:30am on Sunday.
Three white men, aged approximately 16 to 20 years, arrived at McDonalds on foot but could not be served and were told that the restaurant was closed to the public.
They then became abusive and one of the offenders caused damage to a window.
A 26-year-old woman was verbally abused and pushed by the offenders but did not require hospital treatment, and a 26-year-old man who attempted to assist her was assaulted and sustained a serious facial injury.
He was taken to Walsgrave Hospital for treatment.
The offenders made off on foot in an unknown direction. One of the offenders is described as:
Slim build, approximately 5ft 6in tall, short dark hair, wearing trainers and a dark coloured tracksuit with a logo on the front.
It is understood that the restaurant drive-through was very busy at the time.
Officers investigating the assault are eager to talk to any witnesses, and ask that they contact the investigating officer Robert French at Warwickshire Police on 101, quoting incident 0009 of October 12 2014.
Alternatively you can give information without giving your name by calling Crimestoppers anonymously on 0800 555111 or by visiting their website www.crimestoppers-uk.org.