OSCEOLA, Ark. (AP) _ A plane owned by Mayor R.E. Prewitt was destroyed by an explosion early today, and an unexploded bomb was discovered shortly afterward taped to the mayor's car, state police said.

Prewitt told a friend that he was going to go check on the airport explosion when he spotted a white plastic bag with black tape under his car, said the friend, state Sen. Mike Bearden. Prewitt reported that a fuse attached to the bag had fizzled, he said.

''Apparently the fuse went out,'' said state police Lt. Jim Jenkins. He said Prewitt spotted the bomb as he backed out of his driveway.

Authorities did not know if the plane explosion at 3:30 a.m. was related to a recent arson that gutted Osceola's City Hall. Jenkins also said the mayor's plane is very similar in color, shape and description to a plane bombed less than a month ago at the airport.

''At this point, we suspect it was mistaken identity on the airplane a month ago,'' he said.

A woman who answered the phone at the City Hall number said the municipal offices had been moved to a branch bank building. She said that building was checked today along with the mayor's business office.

''This has really thrown us for a loop,'' said the woman, who refused to identify herself. ''With City Hall and now this, we don't know what to think.''

She said the mayor had been in office about 16 years.

Jenkins said agents of the federal Bureau of Alcohol, Tobacco and Firearms were dispatched to look into the airport blast.