A four-year-old girl, the last of five people remaining at Hawke's Bay Hospital after two trucks collided near Lake Tutira on Friday, was discharged from hospital this afternoon.

The five people, including two pre-schoolers, were transported to Hawke's Bay Hospital in two separate rescue helicopters after the collision on State Highway 2 north of Napier at 10am.

Lowe Corporation Rescue Helicopter general manager Ian Wilmot said a light truck collided with a larger dump truck.

A large tow-truck that happened to be travelling past the accident scene helped pull the two vehicles apart, helping the fire service free two passengers trapped in the smaller truck.