Three trucks have been involved in crashes in Waikato

Police are on their way to Kakaramea Road - about three kilometres south of Whatawhata - where two trucks have collided and one driver is believed to be trapped.

One truck is in a paddock and the other is across the road.

Drivers are asked to avoid the area.

Meanwhile further south a serious crash between a truck and a car has closed State Highway One in Tokoroa.

Police were called to the scene - between Tamatea Road and West Road - at quarter-past-four .

Police are unable to say at the moment how many people are in the vehicles and whether they're injured.