The victim was Jennifer Battista, 41, of Milford, said Meredith Daniels, a spokeswoman for Metro-North.
No official cause of death has been issued, Daniel said. But the death "does not appear to be criminal or accidental," she said.
The accident occurred at about 1:42 p.m. Tuesday just west of the Southport station, she said.
Battista was hit by a northbound Amtrak train that left Richmond, Va., at about 6 a.m. and was due in Boston at 4:35 p.m., Daniels said.
Both Amtrak and Metro-North trains were stopped for about an hour in the area after the accident, then service resumed with delays, Daniels said.
At 3:35 p.m., the 200 passengers aboard the Amtrak train were transferred onto another Amtrak train. They were ultimately delayed about two hours to their final destination, Daniels said.
Two other people have been killed by trains on the New Haven Line in Connecticut in recent weeks.
On Sept. 9, the Rev. Colin McKenna, a 50-year-old priest in the Diocese of Bridgeport, was killed when he was struck by a Metro-North train near the Westport station in what was called a possible suicide.
On Aug. 7, Tamar A. Louis, a 28-year-old Stamford resident, was killed when she was hit by a train at the Cos Cob station in Greenwich after lowering herself onto the tracks to retrieve a dropped item. The medical examiner's office ruled her death a suicide.
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