An elderly couple died in one car have been identified as Paul and Lois Grimmer.
The three people in the other vehicle were Piata Ofufangavalu, Cheyene Love-Mitchell and Suliasi Lefai. Suliasi and Piata were of Tongan heritage.
The crash happened at 4.44pm on Tuesday on State Highway 3 in Ōhaupō, about halfway between Hamilton and Te Awamutu.
Waikato road policing manager Inspector Jeff Penno said the two cars collided after one crossed the centre line. But he said the cause of the crash could go unknown for months.
“We understand the time it happened, where it happened, how it happened – but we don’t know why it happened,” Penno said.
Police would check whether either driver was impaired.
“While we always look at the environment, early indications are that roading factors on this particular piece of road are not at fault.
“Impairment is always something we look at, to ensure all drivers are sober, not just alcohol but illegal and legal drugs and that is certainly a focus of this accident.”
The Serious Crash Unit had conducted a “meticulous scene examination” on Tuesday night.
“And the findings from that examination and forensic evidence obtained will feed into a crash investigation, which is likely to take several months,” Penno said.
