A derailment in the Long Island Rail Road's Long Island City yard caused a pair of cancellations at the start of afternoon rush hour on Wednesday.
Marjorie Anders, a spokeswoman for the Metropolitan Transportation Authority, said the incident happened at about 4 p.m.
She said the yard houses diesel engines that pull trains along branches that do not have an electrified third rail. Two trains, one heading to Oyster Bay and a second to Port Jefferson, were cancelled.
The service affects about 2,100 riders, she said. They were advising riders from Penn Station to take another train to Jamaica where they can pick up an eastbound diesel.
Others could take the No. 7 train from Long Island City to Woodside and then catch an LIRR train to Jamaica. Extra trains are stopping at Woodside .
As of 6:35 p.m. on Wednesday a crane was on-site to get the engine back in the tracks once investigators had taken all necessary photographs and measurements to begin their investigation into the cause.
Anders said the MTA is apologizing to riders who have been inconvenienced.