Service is back on parts of the Long Island Rail Road following Saturday night's derailment that sent dozens to the hospital.
The MTA says limited service was restored to the Port Jefferson, Ronkonkoma and Oyster Bay lines in time for Monday morning's rush hour.
Governor Cuomo says crews worked around the clock to repair a damaged rail on one of the tracks.
The derailment happened around 9 Saturday night in New Hyde Park.
Officials say a commuter train side-swiped equipment on a work train that was on the adjacent track.
The Governor says 600 passengers were on board. Thirty-three people were hurt, including four seriously.
The National Transportation Safety Board is investigating.