A fire, which was reported as a bomb, resulting in heavy smoke on the Girard Avenue subway station has diverted trains on the Broad Street SEPTA line.

The fire started on the platform about 2 p.m. in a student’s bookbag, said SEPTA spokesman Richard Maloney, who did not yet have further information.

Shuttle buses are replacing trains between the Erie Avenue and Walnut-Locust stations until regular service resumes, SEPTA said.

The Route 15 trolley/bus, which runs along Girard Avenue, and the Broad Street spur have also been disrupted.