Jefferson County sheriff's deputies are investigating the background of the Idaho Falls pilot they believe went on a three-hour joy ride in a stolen airplane early Thursday.

The 39-year-old man was in fair condition Saturday at Eastern Idaho Regional Medical Center with a broken leg and lacerations.A Jefferson County sheriff's spokeswoman said a single-engine airplane was stolen from the Rigby Airport about 11:30 p.m. Wednesday.

Motorists in Madison, Jefferson and Bonneville counties reported a plane swooped low over them between midnight and 2 a.m. Thursday.

A witness said a single-engine plane flew between the Idaho Falls Temple of The Church of Jesus Christ of Latter-day Saints and the adjacent towers of the former Riverview Hospital building about 12:30 a.m. Thursday.

The plane is believed to have crash-landed about 2:30 a.m. near Ucon when it ran out of fuel.

Bonneville County sheriff's deputies responding to a report of a prowler shortly after 6 a.m. Thursday found a man lying on the back porch of a farmhouse.

A sheriff's report said the man told officers he was on a secret assignment and was doing some advertising when he crash-landed, the report said.