An Alabama school bus driver is dead following the crash of a bus that had just dropped off students at school.

Mobile County school officials tell news outlets the wreck happened Thursday morning near Interstate 65 at U.S. 45. Photos show a crumpled yellow bus lying on its roof on the side of a road.

The Alabama Education Association says on Twitter that the driver was killed, but authorities haven’t released the person’s name.

School spokeswoman Rena Phillips says the driver had just taken students to school when the accident happened.

Authorities haven’t said what might have caused the crash.