Authorities said it started shortly after 4 p.m., at the 125th Street and Lexington Avenue subway station, where the 4, 5 and 6 trains pass.
In the first incident, around 4:12 p.m., a man was seen coming out of the train well of the uptown-bound 5 express train. He had injuries including a broken pelvis and deep lacerations to his buttock and leg. A train was coming into the station at the time, but police said it was unclear if the train had hit him.
NYPD spokesman Paul Browne said the man couldn't tell authorities how he had ended up on the tracks and appeared to be intoxicated.
Shortly afterward, around 4:30 p.m., a 31-year-old Bronx man who had boarded a departing train at that station on the other side of the platform was killed when he fell between train cars and was killed.
Browne said a witness told police the man had been between the cars defecating when he lost his balance.
There was confusion over accounts that there had been a fight between the men leading to the incidents, but police said there was no evidence of that.
"As far as we know at this point, they're separate incidents," Browne said.
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