PHOTO: JULIE ASHER
A police spokesman said two vehicles collided about 5pm.
He was not able to say how many people were injured, or how seriously they were hurt.
"At this stage, that's not something that we're able to confirm."
Traffic was backed up on the Cromwell-Clyde highway.
The spokesman said the road was likely to be closed for some time and motorists were asked to avoid the area and expect significant delays as no detours were available.
The road reopened about 9.30pm.
