A tug boat struck the Susquehanna River Bridge Wednesday night, delaying trains from crossing between Cecil and Harford counties for about an hour.
Four Amtrak trains and one MARC train were delayed as an engineer inspected the bridge and the two tracks atop the structure, Schulz said.
Normal service resumed at 11:20 p.m. after the inspection was complete.
An earlier version of this story misstated the number of tracks on the bridge. The Sun regrets the error.