One person has died in a two-vehicle crash involving a truck in Glenbrook this morning.

Police were called to Glenbrook Road, Glenbrook, around 6.40am.

One person died at the scene, police said.

Fire and Emergency NZ said the crash involved a car and a truck. Fire trucks from Papakura and Waiuku attended.

The road was closed and police asked drivers to take an alternate route via Morley Road.

"The Serious Crash Unit is at the scene and the circumstances of the crash remain under investigation," police said.

In a separate incident, State Highway 1 was blocked at Sunset Road after a crash on Auckland's North Shore. At 7:20am cars were moved to the shoulder but delays were still expected until it was fully cleared.