A 21-year-old woman fought off what is believed to be a sexually motivated attack by biting a man in Christchurch last night.
Police are investigating the incident in Waltham, which occurred between 10.15pm and 10:30pm.
The woman was attacked from behind by a man as she walked along Vienna St towards Hastings St, police said.
"It is believed the assault was sexually motivated," police added.
During the incident the woman was able to bite her attacker's hand and believes she bit hard enough to have left a noticeable mark, police said.
The offender was described as slim, tall (between 6'2 - 6'4), with medium-length, shaggy hair. He was also wearing dark clothing.
Police wished to speak with witnesses and anyone who knows, or has seen somebody with a visible bite mark on their hand.
People with information can contact Detective Constable Chris Healey on (03) 363 7400 or anonymously via Crimestoppers on 0800 555 111.