One person, in a serious condition, has been airlifted to hospital following a crash on State Highway 25 near Thames.

SH25, the Thames Coast Road, was closed near Kereta while emergency services attend a crash reported at 12.45pm.

"Initial indications are that there have been serious injuries in the crash involving a vehicle and a motorcycle," a police spokesperson said.

"Hato Hone St John were notified of a motor vehicle incident at 12.40pm today on Thames Coast Road, Kereta," a Hato Hone St John spokesperson said.

"Two ambulances, one operations manager and one helicopter attended. Two patients, in a minor condition were assessed and treated at the scene and one patient, in a serious condition, was airlifted to Waikato Hospital."

"Roads are open now after a previous serious crash on SH25 at the intersection of SH25 and Russek Rd," an NZTA Waka Kotahi. 

Motorists were advised to avoid the area and expect delays.