A truck driver in Ohio has been charged with aggravated vehicular homicide in a chain-reaction crash involving a charter bus filled with high school students that left six people dead and 18 injured.

The crash on Interstate 70 last November killed three students on the bus and a teacher and two chaperones who were in a vehicle hit by the tractor trailer.

Jacob McDonald, of Zanesville, was indicted Thursday on charges that also include vehicular assault and is being held in jail on a $1 million bond. Court records did not list an attorney for McDonald. Calls to listings for McDonald were not answered.

According to state investigators, McDonald failed to slow down in traffic, struck a vehicle and pushed it into the bus, which was carrying students and chaperones from the Tuscarawas Valley Local School District in eastern Ohio.

Five vehicles were involved in the crash in Licking County, east of Columbus.