Metro-North and the Federal Railroad Administration are investigating the cause of Wednesday night's minor trail derailment at Grand Central Terminal.

No injuries were reported among the 5:19PM Harlem Line train's passengers after two cars came off the tracks at a switch on the terminal's upper level. The derailment blocked New Haven Line trains, leading to delays and crowded conditions.

The Connecticut Post reports a second derailment occurred on an unoccupied train Thursday morning.

Sen. Richard Blumenthal (D-Conn.) released a statement, noting Wednesday's incident called to mind past Metro-North safety concerns. In December 2013, a train that left the Poughkeepsie station derailed near the Spuyten Duyvil station, killing four people.

"Much more than a minor inconvenience, this disturbing multiple car derailment delays and disrupts travel for countless riders," Blumenthal said. "The derailment, fairly or not, recalls past incidents – renewing concerns about safety and reliability."

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