Police, Fire and Ambulance are at the scene of a serious vehicle crash on State Highway 1, approximately 3.5 kilometres north of Hampden, North Otago.
The crash involved a truck and trailer and a tractor in a 100kph speed limit area.
The road has been closed while emergency services deal with the people involved and the vehicles.
Police said that due to the location of the crash, there is no detour available for other motorists. It is expected that the road will be closed for approximately 2 hours.
Police would like to warn motorists that intend to or are travelling in the area to exercise caution as there will be a long backlog of vehicles in both directions.
Patience is requested while emergency services staff deal with the scene. They are working in an expedient manner to open the road as soon as possible.
No further details are known as at 5.45pm.
The Oamaru Mail understands, from a witness, the accident allegedly happened while the vehicles were crossing a bridge.
A bystander said he saw another vehicle attempting to move the truck out of the way.
"It was a bit of a mess and traffic was banked up all the way to Hampden."
Ambulances and other emergency services, including a helicopter, attended the scene but at the time of going to print no information was available on the state of the injuries sustained by the occupants of the two vehicles.
The bridge was closed after the accident and traffic was backed up as a result.
Police were unavailable for comment.