Aaron Donovan, a Metro-North spokesman, said there was an unresponsive customer in the bathroom of the Stamford-bound local train that departed Grand Central Station at 2:37 p.m.
MTA police were notified and Emergency Medical Services personnel responded, Donovan said.
The train was delayed about 20 minutes. EMS met the passenger at the Larchmont station, and the passenger was then transported to Sound Shore Hospital, according to MTA spokeswoman Nancy Gamerman.
There were no other trains delayed as a result of the incident, Donovan said.
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