A man's body has been found at the Waimakariri River in North Canterbury.
Police said the body was found shortly before 10pm yesterday in the riverbed near Harrs Road, west of Kaiapoi.
Detective Inspector Corrie Parnell said police had started a homicide investigation, and the identity of the dead man wasn't yet confirmed.
The scene is under police guard and forensic examination will take place over the coming days.
Police wanted to hear from anyone who was near Harrs Road and South Eyre Road yesterday evening between the hours of 8pm and 10.30pm.
They said the body was not that of Christchurch man Michael McGrath, who has been missing since May and has been the subject of a massive investigation.
A local resident said the discovery brought back memories of the murder in 2008 of Marie Davis, a teenager whose body was found in the river that April.
The resident, who did not wish to be identified, said cars were sometimes driven down the road and set on fire.
She said she was not afraid but did not walk along the riverbank by herself.
Christchurch roading worker Dean Stuart Cameron was convicted in 2009 of the rape and murder of Ms Davis.