The NYPD is offering a $10,000 reward for information leading to the arrest and conviction of the suspect responsible for fatally shooting a beloved school crossing guard aboard a train in Brooklyn two months ago.

Police say the suspect got into an argument with another passenger and opened fire on the No. 3 train as it approached the Rockaway Avenue station in Brownsville.

Elected officials say 45-year-old Richard Henderson tried to intervene but was fatally shot by the suspect.