Edgefield County, S.C. (WJBF) – The Edgefield County Sheriff’s office is trying to find out what caused a school bus to catch fire early Friday morning.

It broke out shortly after four am Friday in the parking lot at JET Middle School in Johnston, South Carolina.

Chief Investigator Randy Doran, with the Edgefield County Sheriff’s office, says three nearby buses also were damaged.

Investigator Doran says it’s believed an electrical problem in the engine of one bus sparked the fire that quickly spread to the buses nearby.

Doran says right now foul play is not suspected.

As a precaution, surveillance video of the school parking lot will be reviewed.