Passengers injured after bus rolls at Tongariro National Park

Twenty people have been injured in a shuttle bus crash near the Turoa ski field on Mount Ruapehu.

The bus, operated by Ruapehu Alpine Lifts, was driving downhill on Ohakune Mountain Road carrying 31 passengers from the Turoa ski area when it rolled.

A St John spokesperson told Newshub four of the injured have been taken to Waikato Hospital, with one in a critical condition.

Emergency crews, including five helicopters, were called to the crash just after 2:30pm on Saturday.

The road reopened at 5:30pm with one lane available to the 1000 people who had been previously stranded on the mountain. 

According to the Mt Ruapehu, Whakapapa & Tūroa Ski Areas Facebook page, all visitors have now safely left the ski field.

Turoa ski field will not reopen until Monday, while the safety of shuttle buses are reviewed.

A fire spokesperson earlier said four people had serious injuries, while Ruapehu Alpine Lifts chief executive Ross Copland said staff were treating 20 patients.

St John has set up a base in Ohakune.

Newshub.