Two patients were taken to Palmerston North Hospital, one in a serious condition, following a crash in Sanson on Sunday.
Hato Hone St John was notified of a crash on Mount Stewart Halcombe Road at 6.23pm.
It sent two ambulances, one rapid response unit and one operations manager to the scene.
Two patients, one in a serious condition and one in a moderate condition, were transported to Palmerston North Hospital.
One further patient in a moderate condition was assessed and treated at the scene, with no transport required.