Nine Gainesville city school buses were damaged by an early-morning fire Friday that investigators said could have been caused by arson.

Eight of the buses were destroyed in the system’s bus lot.

Buses did not run in the morning for the last day of school but did take students home after school.

The state fire marshal’s office is assisting the Gainesville Fire and Gainesville Police departments in investigating the cause of the fire in the Woods Mill Road lot near Gainesville Middle School. It has not been determined if the fire was a result of arson or caused by an electrical problem, investigators said.

State Insurance Commissioner John Oxendine said at a news conference in the bus lot that his office is offering a $10,000 reward to anyone with information leading to a conviction in the case. Anyone with information is asked to call the office’s toll-free tip line at 800-282-5804.

The Gainesville Fire Department received a call at 4:30 a.m. Friday reporting that the buses were on fire, Fire Chief Jon Canada said. No one was injured.

"We’re doing a joint investigation to get to the bottom of what happened at 4:30 this morning," Oxendine said. "Right now, we don’t know a lot."

Oxendine said investigators are reviewing video surveillance footage taken Friday morning at the scene of the fire. He did not comment on whether an individual can be seen in footage of the bus lot when the fire began.

"We are not saying this is arson at this time," he said. "... It’s very unusual to have an idle bus ... to spontaneously combust. That is very unusual. But at this point, it’s premature to say whether this is arson or not."

Canada said a garbage man emptying dumpsters near the bus lot saw the fire and called 911 at 4:30 a.m. He said firefighters were able to put out the blaze shortly after they arrived.

School bus drivers regularly report to the lot for work shortly after 6 a.m.

"This would probably not have been discovered until school officials had arrived at 6, 6:30 to open up school," Canada said.

He said the fire could have quickly spread to more buses in the secluded lot if not for the emergency call.

Gainesville schools Superintendent Merrianne Dyer said although Gainesville school buses did not take children to school Friday morning, the undamaged buses took children home in the afternoon.

"We wanted to check all of them out," she said. "Just to be on the safe side, the fire department recommended we check out all of our buses."

Canada said the buses not involved in the fire were found to be in good condition.

Dyer said an automated phone message system informed parents between 6:15 a.m. and 6:45 a.m. that buses would not pick kids up for school.

Parents took some children to school. Others walked. Dyer said students who weren’t able to get to school will receive an excused absence. Make-up exams for a few high school students will be scheduled next week as necessary.

Dyer said schools reported 91 percent of their students still made it to class Friday.

Frank Machado, who has driven a Gainesville bus for four years, arrived at the bus lot about 6 a.m. Friday morning. He said everything was fine at the lot when he left it at 5 p.m. Thursday.

Machado’s bus, No. 921, was partially burned in the fire.

"This is the one day we look forward to and say goodbye to the kids," said Machado of the last day of school. "We let them scream and have fun."

Machado arrived at work ready for a fun day. He was wearing a bright red hat with the Gainesville logo and a red T-shirt that read, "The Driving Force behind Big Red."

"It’s horrible," he said. "It’s a sad day in Gainesville right here."

School board member Maria Calkins also was saddened by the news.

"It just breaks my heart," she said. "So many children with their gifts for their teachers and saying goodbye to their friends can’t get to school."

Susan Gilliam, principal of Centennial Arts Academy, said the elementary school’s fire alarm sounded at about 5:30 a.m. Friday. She called it a coincidence that the school’s air conditioning unit malfunctioned and emitted some smoke, setting off the alarm.

Gilliam said she was relieved when the fire department arrived to the school and found no damage. She said the school day continued uninterrupted.

Dyer said the nine buses damaged range in value from $65,000 to $90,000 each, depending on age. They made up 20 percent of the Gainesville system’s fleet, leaving 38 in good condition.

The school system’s insurance agent was on the scene Friday morning to evaluate the damage and investigate the source of the fire, Dyer said. She said it will take some time to replace the buses.

"We are very thankful we do not have to get our act together by Monday," Dyer said.