Authorities have identified a man and a woman killed Tuesday when their four-wheel-drive vehicle rolled off a Provo Canyon cliff.

KILLED:Darin Meldrum, 18, Orem.

Sharee Wagenmen, 23, American Fork.

A Utah County sheriff's office report says their vehicle was northbound about 8 p.m. Tuesday on a dirt road above the Olmstead power plant at the canyon mouth when it left the road, rolled several times and went over a cliff.

An Orem city employee found the victims still in the vehicle Wednesday afternoon.

Authorities offered no explanation for the cause of the accident, but some reports said mechanical failure had been ruled out. The road is not restricted and is not considered dangerous under normal circumstances.