Two people have been seriously injured after two cars collided near the Karangahake Gorge.

The crash occurred on State Highway 2, about 7km south of Paeroa this evening. Emergency services are still working at the scene.

Police said motorists should avoid the area or expect delays. Large numbers of cars were expected to be on the state highway over the long weekend.

New Zealand Transport Agency said the crash was blocking the road at the intersection with School Rd. Traffic was backing up at the spot.