Invercargill Police are seeking witnesses to a serious crash on North Road (SH6) yesterday evening.

Emergency services responded to a report of a green Holden Commodore going off the road between Beaconsfield Road and Lorne Dacre Road at 7:45pm.

All four occupants of the car were injured, and two remain in hospital in a serious but stable condition.

"An investigation into the circumstances of the crash is now underway, and Police would like to hear from anyone who has information which can help," a police spokesperson says.

"If anyone witnessed this crash or remembers seeing the Holden Commodore in the area between 7:15pm and 7:45pm, they are urged to get in touch.

"We would also like to hear from anyone who may have any dash-cam footage."

Witnesses can contact police on 105 quoting file number 210706/3946.