The train derailed as it was moving through the West Side Yard on Saturday evening, leaving two cars in the middle of the train off the tracks.
There were no passengers on board the train at the time, but one LIRR employee suffered back pain.
As a result, eight trains were canceled or partially canceled during the Monday morning rush. The LIRR also announced seven trains would be canceled during the evening rush.
As they scrambled for their rush hour trains Monday night, many riders insisted they had a right to know, that the MTA had an obligation to inform the public after a commuter train tumbled off the tracks in the railyards just west of Penn Station.
The train was out of service at the time, being moved to a platform inside Penn Station to take on passengers. Damage to the tracks and switches was extensive.
Yet railroad officials did not acknowledge the derailment for nearly 24 hours, until after Eyewitness News posted photos on social media and later on television and online.
The railroad president defended his response, insisting that his priority was to oversee the repair operation and that weekend service was unaffected.
He later told reporters that his staff needed to develop a contingency plan for Monday's rush hour.
An investigation into the cause of the derailment is underway.
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