Investigators suspect arson in an early morning car fire in Missoula.

Police said a fire started in the back seat of a 1999 Acura  about 6 a.m. Monday.

It happened at South 5th Street West and Johnson. A passerby called police.

When firefighters and police arrived, nobody was in or near the vehicle. Nobody was injured.

Fire and police said the circumstances are suspicious, although at this stage, investigators have no suspects.

If you have any information, call Detective J.C. Denton at 552-6292.