Police in Brooklyn need help finding two people they say attacked a man with a hammer and robbed him in Brooklyn.

Investigators say the 64-year-old victim was approached by a man at the corner of Dean Street and Fourth Avenue in Boerum Hill Wednesday afternoon.

Police say the attacker, seen in surveillance video above, demanded money, but the victim didn't have any.

That's when they say the man hit him in the head with a hammer, knocking him to the ground and breaking his jaw.

The man and a woman then took the victim's cellphone and ran off, authorities say. 

The man is described as six feet tall and about 170 pounds.

Police say both he and the woman were last seen wearing dark clothing.

Anyone with information on the case should contact the Crime Stoppers hotline at 1-800-577-TIPS, or text CRIMES and then enter TIP577, or visit www.nypdcrimestoppers.com.