A nightclubber has been subjected to a serious sexual assault as she enjoyed a night out with friends in a busy town centre club.

The 23-year-old was attacked during a night out in Stockton.

At around 1.30am last Saturday the woman was chatting to a man in the upstairs bar of the Zanzibar Nightclub in Stockton High Street when he led her to a back stairwell, through the club's emergency exit, where it is believed the incident took place.

The woman is then thought to have blanked out for several minutes. When she came too she went back to find her friends and went home, where she called the police.

The man is described as 6ft 5ins tall, in his early 20s, with short hair and blue eyes. He was wearing either a black or dark blue shirt.

PC Francesca Donovan, from Stockton Police, said: "This was a frightening ordeal for this woman who was feeling very vulnerable.

"CCTV has revealed some evidence of a man matching his description, but we hope that by doing this appeal drinkers who were in the club may be able to help."

Anyone with any information should contact PC Donovan on (01642) 302226.