Police are appealing for witnesses following a traffic incident in Southland.

A large four-wheel-drive vehicle was seen speeding and driving on the wrong side of the road with its lights off on State Highway 6 at Ryal Bush about 7pm yesterday.

The vehicle was a light colour at the front, possibly white, with a dark-coloured rear deck.

It also appeared to have a large object on the deck.

Anyone who may have witnessed the incident is asked to contact Senior Constable Blair Walker at Invercargill Police on (03) 211 0400.