Police will be looking at whether anyone was wearing seatbelts on a bus which crashed yesterday near Rotorua, killing five Chinese tourists.
The accident happened after the tour bus failed to take a moderate to easy bend, and lost control rolling off the road on State Highway 5 between Waiohotu and Galaxy roads around 11am.
Two of the 27 tourists on board remain in a serious condition in hospital.
The "medium-sized" tourist bus contained Chinese nationals and the driver of the bus is not seriously injured.
There were no other vehicles involved in the accident.
Police say the road will remain closed for a "considerable amount of time" as investigations continue.
Work is taking place with the Ministry of Foreign Affairs and Trade and the Chinese Consulate to identify the victims who died and notify their next of kin.
The Chinese Embassy in New Zealand issued the following statement to 1 NEWS after the fatal crash yesterday: "The Embassy attaches great importance to the tragic incident. Our deep condolences with those who died and injured.