Car crashed off the Whanganui City Bridge into the Whanganui River.
The Police Dive Squad have recovered a truck from the Whanganui River after the vehicle plunged into the water on the first hour of Christmas Day.
Police have confirmed one person, a male, was found inside.
"Indications are he was the sole occupant. Enquiries into the circumstances of the crashare ongoing," police said in a statement.
"Police would like to speak with anyone who witnessed the crash or who has information that may be of assistance."
Anyone with information can get in touch with Whanganui Police on (06) 349 0600. Information can also be given anonymously via Crimestoppers on 0800 555 111.
Whanganui District Council announced earlier this morning local iwi had imposed a rahui, a ban on fishing and using the river, which would likely be lifted on December 27.
Such measures are often enacted after someone has died.
Emergency services were called to Victoria Ave Bridge near Anzac Parade in Whanganui about 12.21am after reports a car went into the river, a police spokesman said.
Police Dive Squad and Fire and Emergency New Zealand have recovered what appears to be a 4x4 truck from the Whanganui River on Christmas Day afternoon. Photo / Bevan Conley
The Police Dive Squad arrived on site about 1pm.
An emergency services staffer at the scene said it was "a sad start to Christmas".
The Police Dive Squad had been called in to assist the search and police are likely to remain at the scene for some time. Photo / Simon Waters
Local iwi have imposed a rahui. A ceremony was held mid-morning.
The crash location has been the scene of previous accidents in 2007 and 2010.
A gap in the City Bridge's railing was caused by a car which hit the railing in a 2007 crash. No injuries were reported in that accident. Photo / File
Meanwhile, a person was taken to hospital in critical condition after a crash on Main North Rd in Canterbury about 1.30am.
A police spokeswoman said it appeared a car went through a fence into a field.
Rescue services deal with a crash on the City Bridge in 2010. Photo / File
The Serious Crash Unit had examined the scene and inquiries were ongoing, she said.