The driver of the Golf, a 30-year-old Indian man from Rotorua died at the scene of the crash yesterday, Western Bay of Plenty road policing Senior Sergeant Ian Campion said.
Another 31-year-old Indian man from Rotorua travelling in the car suffered critical injuries in the crash and died at Waikato Hospital at 11.20pm last night.
Two female passengers in the car remain in a critical condition. A third man suffered minor injuries.
The names of those involved in the crash have not yet been released.
The tanker driver escaped without injury and was receiving support from Victim Support, police said.
Western Bay of Plenty area commander Clifford Paxton said the crash was tragic and he urged motorists to take extreme care on the roads.
Three hours later, a 56-year-old man died after his motorcycle and a car collided on State Highway 7 at Hurunui, just north of Christchurch near the Marble Point Winery.
The Harley Davidson was travelling towards Hanmer Springs and the car towards Christchurch. The motorcyclist was flown to Christchurch Hospital by the Westpac Helicopter in a critical condition and died soon after.
The five occupants of the car, who were all wearing seatbelts, were not injured.
On Saturday, a back-seat passenger in a car was electrocuted while climbing out of a vehicle that crashed into a power pole in Glentui in the Waimakariri District. He was last night named as Jamie Shane Webb, 25, from Christchurch. A spokesperson for his family said: "Jamie will be sadly missed by all of his friends and family."
On Boxing Day, a man died at Whakamarama in the Bay of Plenty when the rental car he was driving and another vehicle collided, critically injuring an elderly Omokoroa couple.
The 70-year-old man and the 74-year-old woman were yesterday in serious conditions in Tauranga Hospital.
The same day, a car being driven by a 22-year-old Chinese woman collided with a campervan at the intersection of State Highways 97 and 6 in Southland. She died in hospital on Saturday.
The holiday road period started at 4pm on Christmas Eve, and runs until 6am on Monday, January 5.