A person has died following a crash southwest of Allanton early this morning.

The two-vehicle collision occurred on Allanton–Waihola Road, State Highway 1, at about 1am.

Police said the Serious Crash Unit is investigating and the road remains closed while emergency services work at the scene.

According to NZTA, State Highway 1 is closed between State Highway 86 and the Henley Berwick Road intersection. Motorists are advised to plan their journey accordingly and allow extra time for travel.

The detour for southbound traffic is via State Highway 86 (Centre Road), turning left onto Henley Berwick Road and then right back onto State Highway 1. For northbound traffic, the same route applies in reverse.