The police dive squad retrieved two bodies from the river last night and this morning after a car with four Mongrel Mob members plummeted into the Mohaka River.
State Highway 2 at Mohaka was closed from 4pm to 6pm today so a crane could retrieve the car from the river.
The car plummeted 150 metres down a cliff face into the Mohaka River between 2:30pm and 2:45pm.
One man is confirmed dead, and one was injured and taken to Wairoa Hospital in a moderate condition. He has now been discharged.
The other two were trapped in the car before being retrieved last night and this morning.
Police believe the incident may be a result of foul play, in which the vehicle was run off the road.
3 News understands there was too much debris at the scene to have come from just one vehicle, and after initial inquiries police are now looking for a blue Japanese-made car.
Detective Sergeant Brent Greville says police are keen to speak to anybody who may have seen the crash occur, or noticed any other vehicles in the area around the time of the incident.
Police know the identities of the crash victims, but will not release any names while they liaise with families.
The men were heading to the 50th anniversary of the Mongrel Mob when they drove off the road.
Earlier this week, the event was granted a controversial liquor licence to serve the 400 expected attendees.
There have been no police callouts as a result of the celebrations.