COLUMBIA, S.C. — An Army trainee has been arrested after authorities say he boarded a South Carolina school bus with a gun Thursday and held the driver and elementary students hostage before letting them off the bus.

During a news conference, Richland County Sheriff Leon Lott said the incident started at around 7 a.m. near Fort Jackson, the U.S. Army’s largest basic training facility, located in Columbia. The trainee, dressed in physical training clothes, “ran off post and escaped” with a rifle from the installation, Lott said. Deputies then started receiving calls about someone standing on a nearby interstate flagging down cars.

The trainee then went to a nearby bus stop where children were waiting to be taken to Forest Lake Elementary School, Lott said, and boarded the bus himself, armed with the rifle.

“He told the bus driver he didn’t want to hurt anybody; he wanted him to drive him to the next town,” Lott said.

After some of the children asked repeatedly if the trainee planned to hurt them or the driver, the trainee “got a little frustrated” and ordered the bus stopped, allowing the driver and children to get off, Lott said. He then drove the bus several miles before abandoning it, with the rifle inside.

The trainee’s name has not been released.