Police say a black man in his 20's stepped on the BX-41 bus through a rear door without paying the fare. When Diaz called him on it, the suspect pounced on him.
Surveillance video shows police arriving just minutes after the incident. Investigators said the suspect beat Diaz in the face, slammed his head against a window, and choked him until he nearly lost consciousness.
The suspect ran off, so investigators spent part of the day searching nearby stores that might have caught a glimpse of the man who brutalized a bus driver of 24 years.
As of Thursday evening, the suspect remains at large.
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