A SEPTA train with about 30 passengers on board partially derailed on the Market-Frankford Line shortly after 11 a.m Saturday. There were no reports of injuries.

The train, traveling eastbound from Center City, was arriving at the Spring Garden station when, as it was going through a crossover section — where trains switch from one set of tracks to another — "an equipment problem" caused the lead car to go partially off the track, said SEPTA spokesman Andrew Busch. Earlier reports said the rear portion of the train had derailed.

"Due to previously scheduled work that required single tracking, the train was crossing over from the eastbound to westbound sides when the lead car partially derailed," SEPTA said in a statement issued Saturday afternoon.

Busch did not know how fast the train was traveling but said, "It would have been going very slow there because it's on a crossover and because it's so close to a station."

Passengers on the train were evacuated as soon as power to the tracks was turned off. Emergency personnel escorted them on foot to the nearby train station, Busch said. According to SEPTA, one person was treated at the scene for heat exhaustion and released.

Preliminary indications were that the problem involved the underside of the train where the wheels are housed, Busch said.

As the investigation continued, SEPTA ran shuttle buses between the Eighth Street and Berks stations. For the latest travel information, check @SEPTA or www.septa.org.