A teenage girl was physically assaulted by a large man as she walked through school grounds in Nelson.
The assault happened at Nelson Central School on February 27 between 8.30pm and 9.20pm.
The girl walked along Collingwood St into Nile St through the school, then returned the same way.
She was physically assaulted in the school grounds by a man described as having a large build.
He was wearing a black hoodie, loose-fitting jeans ripped at the knee, and black and white Nike shoes.
Police would like to hear from anyone who saw a man fitting that description in the area around the time of the assault.
Police would also like to speak to an elderly couple the girl saw while walking near 170 Collingwood St.
Anyone who can help is asked to call Detective Green on (03) 546 3841.
Information can also be provided anonymously via Crimestoppers on 0800 555 111.