One person has died after a crash involving a van carrying seasonal workers from Samoa, in Tarawera north of Napier.
St John said they were alerted to the incident on State Highway 5, Tarawera, between Tataraakina Road and Pohukura Road at 9.52am.
Ten people with injuries ranging from moderate to critical were treated by St John, before being transported to various hospitals - including in the Hawke's Bay, Gisborne, Palmerston North and Taupō - via helicopter and ambulance, St John Hawke's Bay territory manager Brendon Hutchinson told 1 NEWS.
A rescue helicopter transported a critically injured man to Hawke's Bay Hospital for further treatment, while two other rescue helicopters transported further patients to hospital, Lowe Corporation Rescue Helicopter Service said on Facebook this afternoon.
A man has since died.
Police say: "Eleven people, including the deceased, were in the van when the crash with the truck occurred.
"A number of those people in the van were Samoan nationals, who were in New Zealand working as seasonal workers. One New Zealander was also in the van."
Five of those injured in the crash are being treated at Hawke's Bay Hospital, a spokesperson for the Hawke's Bay DHB told 1 NEWS.
A teenager remains in the Intensive Care Unit with critical injuries, while four others - ranging in age from 20s to 40s - are in stable condition.
1 NEWS spoke with the owners of nearby Tarawera Cafe who said a truck carrying wine tried to avoid hitting three vans when the accident happened.
State Highway 5 has since reopened.
An investigation into the cause of the crash is ongoing.