A diesel spill is believed to have caused five crashes near Bulls Gorge this morning.
Police said they were managing the spill, believed to have happened about 10am, which appears to begin at the Puketona Junction on State Highway 10.
It is not yet known how far the spill has spread.
No injuries have been reported as a result of the crashes.
Police advised motorists to slow down and be extremely careful in the area and avoid it if possible.
Police were working with NZTA to clean the road.