The Serious Crash Unit is investigating an accident in Waikato, in which a motorcyclist died.

A car and the motorbike collided on the roundabout of Te Rapa and Hutchinson Roads at Horotiu north of Hamilton, last night.

The motorcyclist was trapped underneath the car, and died at the scene.

It was the third motorbike fatality yesterday.

One motorcyclist died in a crash on Auckland Harbour Bridge, and another was killed in a crash at Ohaka in Canterbury.