In each case, the suspect approached a victim, simulated a firearm, demanded and received their personal property, and then fled on foot.
Investigators say he's responsible for 3 armed robberies, one of them near the corner of Greene Avenue and St James Place.
"I usually feel really, really safe. This is the first I've heard about armed robbery," one woman, who lives nearby, said.
She's planning on taking precautions with the suspect still out there.
Police are hoping someone recognizes him so they can make the arrest. He's in his 30's, about 5-9 to 6 feet tall, about 180 pounds and wearing a brown jacket, gray sweatshirt and blue jeans.
Anyone with information is asked to call Crime Stoppers at (800) 577-TIPS (8477). You can also submit tips by logging onto Crime Stoppers' website at www.nypdcrimestoppers.com or by texting tips to CRIMES (274637), then enter TIP577. All calls are strictly confidential.