“While there is not believed to be anyone else outstanding, the Police National Dive Squad will attend to inspect the vehicle,” a spokeswoman said.
St John said it sent a helicopter and ambulance to the crash site at 4.12am.
“Our crews assessed and treated two patients in a moderate condition who were transported to Wairoa Hospital,” it said.
Police said cordons were in place while emergency teams continued their work.
“Motorists should avoid the area if possible.”
Fire and Emergency New Zealand confirmed staff were at the scene after a car was reported as having gone into the Wairoa River about 4am.
“I can confirm there was a vehicle in the river,” a spokesperson said.
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