A serious crash in the Manawatū-Whanganui region this afternoon has killed at least one person.

Hato Hone St John said it was advised of a crash at 12.40pm on State Highway 1, Mangaweka.

Nine ambulance vehicles have been sent to the scene, an incident report says.

“Hato Hone St John [is] responding to a traffic-related incident on SH1 near Mangaweka. Multiple ambulances and helicopters are currently responding to [the] scene,” it said initially.

Police said the crash involved two vehicles and there are multiple people seriously injured in both vehicles.

Multiple people seriously injured

In the latest update, Hato Hone St John said paramedics treated three people. Of those, two victims - one critically injured and the other in a serious condition - were airlifted to Wellington Regional Hospital.

A third person suffered moderate injuries and was taken via ambulance to Palmerston North Hospital.

New Zealand Transport Agency Waka Kotahi confirmed the crash was a “fatality”.

The crash has blocked SH1 north of Mangaweka and the road will be closed to southbound and northbound traffic.

Diversions are being put in place via SH4.

New Zealand Transport Agency Waka Kotahi called the incident a “serious crash” near the intersection of Ruahine Rd.

“Delays are likely, and a road closure is possible,” road authorities said.

Motorists are advised to follow directions given by emergency services, avoid the area, or delay travel.

The detour would be in place for at least two hours.

“NZTA thanks all drivers for being patient on the detour route, which will be busy. If people can delay travel today that will help ease congestion on the detour route.”