A woman has been found dead in Lake Keystone near Sand Springs.
The Highway Patrol says it appears the woman was driving on Hwy. 151 when she ran off the road and her car rolled on the bank.
Investigators believe she suffered a head injury and got out of the car and staggered to the edge of the lake where she either slipped or collapsed and fell into the water.
The woman's name has not been made public.
Investigators say the body will be sent to the state medical examiner to determine the exact cause of death.