An Amtrak train bound for Washington, D.C., bumped an NJ Transit train as it departed New York’s Penn Station at the height of Friday’s morning rush, breaking some windows and causing a minor derailment but no serious injuries, authorities said.

NJ Transit said one of its trains on the Montclair/Boonton line was coming into the Manhattan transit hub shortly after 9 a.m. when the departing Acela sideswiped it between the north tube and the station. Amtrak did not acknowledge the bump in a later statement, but said its Acela Express Train 2151 “had a minor derailment while moving at a slow speed.” The train originated in Boston.

“The rear of the train was still on the platform, and all 248 passengers have exited the train onto the platform and into the station safely,” the statement said. “Service into and out of New York Penn Station will be delayed while we investigate this incident.”