A brave postal worker was shot in the arm when he tried to use his mail truck to stop a crook from carjacking a fellow mail carrier in the Bronx on Tuesday.

The man was driving his US Postal Service truck near 232rd Street and Carpenter Avenue at around 6 p.m. in Wakefield when he attempted to stop the armed suspect from fleeing the scene by blocking him with the vehicle, cops said.

Clarence Brooks, 27 then fired one shot, which grazed the postal worker in the arm.

Brooks had stolen the Honda Accord from another postal worker, who was off duty, on White Plains Road at East 232nd Street.

After firing his weapon, Brooks got around the shot worker’s truck and drove away. Minutes later he crashed the vehicle on 231st Street before fleeing on foot.

Brooks was apprehended just blocks away and was being questioned at the 47th Precinct station house Tuesday night.