PHILADELPHIA (KYW Newsradio) — Authorities are investigating after a brick was thrown at a SEPTA bus along the Schuylkill Expressway in West Philadelphia early Wednesday morning.

Around 3:15 a.m., a Route 2 bus was on I-76 East near Girard Avenue when a person who was walking along the highway threw a brick at the windshield, SEPTA said. The glass on the passenger side shattered.

The bus operator was not injured, and there were no passengers on board, the transit agency said.

The damaged bus was towed away to one of SEPTA’s bus depots. Transit police are investigating. No one was arrested, and a motive was not immediately clear to police.

There were no reports of other vehicles being hit.

Featured Image Photo Credit: SEPTA