Christchurch police are seeking witnesses to the suspicious behaviour of a man who followed a teenager for about a kilometre along a street.
The 15-year-old girl reported being followed on Brookside Road in the suburb of Rolleston from 2.30pm on Monday.
She noticed the man at the intersection with Rolleston Drive and he continued to follow her when she crossed the road several times up until the intersection with Burnham School Road.
Sergeant Grant Stewart says the girl at that point sought help from a member of the public who drove her to her destination.
The man fled in the opposite direction.
He was described as a Caucasian in his 40s, about 1.85m tall and with very short hair or possibly bald.
He was wearing camouflage-coloured trousers and a dark grey-coloured t-shirt, and carrying a camouflage backpack.