LINCOLN COUNTY, Wis. (WTAQ) - A woman died after a car fell into a lake in north central Wisconsin – and authorities are still trying to determine how it happened.

Lincoln County sheriff’s deputies said the vehicle drove into Moraine Lake in the town of Harrison just after 4:45 a.m. Sunday. A man freed himself and called 911. And by the time officers arrived, he pulled the woman from the car. She was unresponsive. Rescue efforts failed, and she died at the scene.

The man was treated at a hospital in Tomahawk and was later released. The victims’ names were not immediately disclosed.