A railroad spokesman says the train's engineer pulled the emergency brake, but the 80-mile-an-hour train slammed into the car, pushing it a half a mile until it came to a rest at the Brentwood station.
Two people in the car, which was engulfed in flames, were burned beyond recognition. Officials were still trying to determine their identities.
The engineer and two crewmen aboard the eastbound train were not injured.
The accident happened around 10 a.m. Tuesday while the train was returning to the yard in Ronkonkoma.
LIRR says close to normal service has been restored on the Ronkonkoma branch.
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