The incident happened shortly after 7:30 p.m. at Nostrand Ave and Beverly Road in Flatbush where the 2 and 5 trains run.
Authorities say the 27-year-old male conductor was semi-conscious and taken to Kings County Hospital where he is in stable condition.
The suspect is a male in his 30s who was wearing a mask, blue jeans and a dark jacket.
Police say the victim was telling the suspect to please not hold the car doors when it led to a verbal dispute between the two on a northbound 5 train.
The conductor was punched, fell and hit his head, according to police. No arrests have been made.
The MTA tweeted out that trains were delayed between Franklin Ave and Flatbush Ave - Brooklyn College as police investigated.
We are restoring regular 2/5 train service between Franklin Av and Flatbush Av-Brooklyn College.— NYCT Subway (@NYCTSubway) March 5, 2020
Given the duration of the disruption, our trains and crews are out of position. That means you should continue to expect longer wait times and/or crowded trains on the 2/3/4/5 lines. https://t.co/5k5vypzjdI pic.twitter.com/s37gOSrLic
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