2011 was the year of the ‘South Slope Sex Fiend’

Fear and loathing filled a large swathe of Brooklyn in 2011 after a rash of violent sex attacks in the South Slope targeted nearly two dozen women while cops fumbled to nab the creeps. Six different “Wanted” sketches — each describing a short Hispanic man in his 20s — clung to area storefronts as police swarmed every corner and subway station in vain.

Pro-active area residents fought back by holding protests, forming buddy systems, calling in the Guardian Angels, and lashing out against police who scolded young women for wearing skirts.

Here’s a look at the brutish spree that rocked Park Slope, Sunset Park, Bay Ridge, and Windsor Terrace — and vanished eerily into the night after just one botched arrest:

March: A sicko tries to rape a woman on 16th Street near Fourth Avenue — a vicious incident caught on a surveillance camera that police didn’t bother to investigate until neighbors leaked footage to the media.

May to August: A fiend attacks five other women and rapes one. After an attempted rape on Aug. 26, police ramp up their hunt, passing out “Wanted” flyers and distributing safety tips. But residents are critical of the tardy response. “It’s too little, too late,” said Aaron Brashear, founding member of Concerned Citizens of Greenwood Heights. Within days of the stepped-up cop campaign, another woman is groped.

September: Residents are as fed up with cops as they were with the gropers after a Kensington woman says that officers manning the Crime Stoppers hotline hung up on her when she called with a tip. A Park Slope woman, attacked on 12th Street near Eighth Avenue, said that police never showed up after neighbors called for help.

That same month, residents form Safe Slope in response to the attacks, conducting street marches and self-defense classes, and providing “safe walks” home.

Oct. 1: Police inexplicably release a key detail about the very first sex attack — seven months later! Irate locals claim that a dozen other attacks could have been prevented had they known about the thug’s colorful varsity jacket and the specific wording on its back.

Oct. 11: Cops arrest 26-year-old Adolfo Martinez, a Mexican immigrant who worked in a Chinatown fish market — a day after he gropes a woman in Sunset Park. Investigators put Martinez through a score of lineups, but only link him to a single attack.

Oct. 14: Cops add six subway molestations to the unsolved crime binge, bringing the number of gropings and attempted rapes to at least 20. A Carroll Gardens woman comes forward on the same day to say she was the fiend’s first victim.

Oct. 17: Police collar a second suspect, a 32-year-old Manhattan bartender they find masturbating between parked cars on 17th Street and 10th Avenue. He is picked out of a lineup and connected to a May incident where a man allegedly grabbed a woman’s breasts and masturbated at the entrance of the Seventh Avenue F train station. Cops drop those charges a few days later after the victim recants her story.

Mid-October through December: The sex fiends who preyed on the area suddenly stop. No additional attacks are reported in Park Slope and Windsor Terrace, although a man on a bike gropes two women in Kensington around Oct. 19.