Authorities are investigating after a SEPTA bus caught on fire in the Penn's Landing area this morning.

SEPTA said the blaze broke out on the Route 33 bus near Front and Chestnut streets shortly before noon.

The bus operator was taken to Hahnemann University Hospital for observation. The nature and extent of his injuries weren't known.

A mechanic responded to the scene when the bus' fire-suppression system didn't completely put out the blaze. The mechanic wasn't harmed, and no passengers were on the bus at the time.

The fire remains under investigation.