The police are investigating an incident in which a nude man approached a school student at a railway reserve at Stoke in Nelson last week.
The police said the man performed an indecent act before the student ran to safety.
The man has been described as being a tall Pakeha in his thirties or forties, with salt and pepper coloured hair, a goatee and a fat stomach.
Detective Sergeant Ian Langridge said he was also seen yesterday at the Tahunanui touch fields, and a railway reserve behind Broadgreen School on Monday.
He said the man poses a risk, and the police will have an increased presence in the area until the he is identified.
