What Happened
A 6:20 a.m. LIRR train from Jamaica heading to Penn Station struck debris on the tracks in an East River tunnel and became stuck behind a disabled NJ Transit train. The debris had been left by the NJ Transit train, which had become blocked in the Amtrak tunnel earlier that morning.
Passenger Evacuation
About 900 passengers were trapped on the LIRR train. The FDNY responded and safely evacuated and removed all passengers using two rescue trains. Passengers were transferred either to a passing occupied train or to an empty rescue train, with commuters directed to Long Island City or Grand Central.
Service Disruptions
The incident caused widespread disruptions across the LIRR system. Eight of the 11 LIRR branches experienced cancellations, delays, or reroutes, including the Hempstead, Babylon, Long Beach, Port Washington, and Ronkonkoma branches. Many trains to Penn Station were canceled or diverted to Grand Central Madison instead. The MTA warned to expect further delays and cancellations Wednesday.
Context
The incident occurred while one of the four East River tunnels was already out of service for Amtrak's three-year tunnel rehabilitation project, expected to last into 2028. This rehabilitation work was prompted by damage from Superstorm Sandy. MTA officials had asked Amtrak to limit rehabilitation work to nights and weekends to keep tunnels available during rush hours, but Amtrak determined that proper work required keeping one tunnel out of service around the clock. 
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