The incident occurred at about 9 a.m. just north of the Beacon Falls train station, Metro-North spokeswoman Nancy Gamerman said.
No information was available on the identity, age or hometown of the female, pending the investigation and notification of family, she said.
The train involved in the accident had left Bridgeport at 8:02 a.m. and was running behind schedule — it had been due to arrive in Waterbury at 8:57 a.m., Gamerman said.
There were no injuries reported among the 35 people onboard the train, and a bus picked up those passengers at Cold Spring Road, she said.
Bus service was being provided on the Waterbury Branch for the 9:12 a.m. train from Waterbury to Bridgeport. It is operating about 30 minutes late, Metro-North said.
It was not known when train service would be restored on the Waterbury Branch.
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