Baltimore school bus crash: No children among 6 dead

Six-dead following bus crash in Baltimore.

(CNN) — A school bus with no children on board crashed into a commuter bus in Baltimore Tuesday morning, killing at least six people, police said.

Authorities are investigating what caused the crash, which occurred around 6:30 a.m., police said.

Video from CNN affiliate WBAL shows the school bus wedged into the side of the commuter bus, with firefighters surrounding the scene.