Emergency services are responding to a serious two-vehicle collision on Tirau Road - State Highway 1 - near Cambridge this afternoon.

Police were notified of the crash at 4.04pm.

"Initial indications suggest two people have serious injuries and two others have moderate injuries," says a Police spokesperson.

Traffic will be diverted and motorists are asked to avoid the area.

At the scene? Phone 0800 SUNLIVE or email newsroom@thesun.co.nz