ALLENTOWN, Pa. (AP) — An electrical beam has collapsed onto several cars inside a highway tunnel in Pennsylvania, causing a major traffic backup.

Police say no one was injured when the beam fell inside the Lehigh Tunnel around 6 p.m. Wednesday. The southbound lanes of the Pennsylvania Turnpike's Northeast Extension tunnel were shut down shortly afterward.

Turnpike electricians are working to repair the beam.

Police say they hope to reopen the southbound lanes by morning rush hour.