A person has been cut from their vehicle in a serious crash that injured three people and closed State Highway 1 in Riverlands, south of Blenheim.
Emergency services, including a helicopter, were called to the scene at 12.15am.
Fire and Emergency New Zealand shift manager Blair Walklin said three crews attended and used hydraulic cutting equipment - the 'jaws of life' - to free one person who was trapped.
A spokesperson for Hato Hone St John said two people with moderate injuries were taken to Wairau Hospital.
A third seriously injured patient was flown to Nelson Hospital.
A police spokesperson said one person sustained critical injuries.
NZ Transport Agency Waka Kotahi said the highway between Riverlands and Redwood Pass remained closed at the Redwood Pass Rd intersection.
It said no detours were available and advised motorists to avoid the area.
