Police are searching for a man who they say seriously injured a 78-year-old man in an attack aboard a B61 bus in Carroll Gardens.

The man started an argument with the 78-year-old on a northbound bus approaching Court Street and West 9th Street just after 12:30 p.m. on Feb. 21.

Authorities say the man then punched the 78-year-old multiple times in the face and body.

EMS took the victim to New York-Presbyterian Brooklyn Methodist Hospital, where he is expected to recover.

The attacker was last seen wearing dark-colored clothing.

Anyone with information is asked to call the NYPD’s Crime Stoppers Hotline at 1-800-577-TIPS (8477).