Police are concerned the so-called serial groper of the Upper East Side is getting increasingly brazen as they investigate a 10th touching incident Tuesday.
In the latest incident, the diminutive assailant allegedly approached a woman from behind as she was entering her building on East 111th Street and called out in Spanish to her, saying "Mami, mami."
The woman pushed the man away, but he grabbed her below the waist before he took off running, said police.
Police Commissioner Ray Kelly said Tuesday that if women are approached by him, they should make noise and stare at him.
"Make sure he becomes aware of someone looking at his face.... As a piece of general advice, I would make noise to scare him off," Kelly said.
Investigators speculate the man may be a kitchen worker at a local restaurant who works odd hours, according to the police commissioner.
The suspect last struck Saturday, approaching a woman in Midtown and lifting her skirt.
Police last month released surveillance video of the suspect. Anyone with information about him is asked to call Crime Stoppers at 1-800-577-TIPS (8477).