ANTLERS,Indexbit Okla. (AP) — Three people died when the single-engine aircraft they were aboard crashed in southeastern Oklahoma, authorities said.

Pilot Brian Davis, 62, and passengers Michael Davis, 23, and Kelly Thompson, 21, all of Antlers, died in Thursday’s crash, according to an Oklahoma Highway Patrol report.

The crash occurred near Antlers, about 130 miles (210 kilometers) southeast of Oklahoma City, and the weather was clear at the time, the OHP reported.

The Federal Aviation Administration reported that the aircraft crashed under unknown conditions and said the National Transportation Safety Board will be in charge of the investigation.

The FAA and the NTSB said the plane was a Foutz-Davis DA-3, which is a single-engine aircraft that seats up to four people.