Police in Wellington are appealing for witnesses to an indecent assault early on Saturday morning.
Detective Constable Trevor Collett says a 17-year-old female was standing at the bus terminus in Courtenay Place at about 3.20am when a white van full of young males pulled up beside her.
He says one man got out of the van, grabbed her and indecently assaulted her.
Mr Collett says she managed to break free and lock herself in the cubicle of a nearby public toilet.
He says the group in the van were noisy and unruly and it's likely someone will remember them. The van was old and shabby, with a black line along its side.
The offender is described as between 18 and 25, Caucasian, with blonde, medium-length hair and about 175cm or 5ft 9in tall.
He was wearing a checked and striped long-sleeved shirt and dark-coloured pants.