Brooklyn

Don’t shake this sicko’s hand.

A subway passenger was busted after he waved his manhood at a female straphanger on a train in Fort Greene, police said.

Champ Osmond, 31, boarded a near-empty southbound 3 train at 7 a.m. Thursday and took a seat opposite a 28-year-old woman, sources said.

Osmond unzipped his pants and exposed himself, the sources said.

He then stood, grabbed himself and approached the woman, cops said.

At the Nevins Street station, the woman flagged down cops.

“She was looking at my s—,” Osmond allegedly told police.

He was charged with public lewdness and harassment, said a spokesman for DA Charles Hynes.

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Police are searching for three thugs who stabbed another teen in the back in East Flatbush yesterday.

The group of knife-wielding teen punks plunged a blade into the 15-year-old victim on East 29th Street near Beverly Road at 3:30 p.m., cops said.

Police arrested two juveniles at the scene but are still looking for another three suspects, authorities said.

The victim was treated at Kings County Hospital.

Bronx

A 27-year-old man shot and wounded a 41-year-old man and then turned his gun on himself, in an attempted murder-suicide in Melrose, police said.

The shooter was found dead around 10:35 p.m. in a hallway of the six-floor building on Avenue St. John near Southern Boulevard.

Moments later, a second man was discovered shot in the shoulder and chest. He was taken to Lincoln Hospital.

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Two thugs were busted for beating a man and a woman outside a South Bronx McDonald’s, cops said.

David Laureano-Rodrig, 19, and Tasheem Holder, 22, allegedly surrounded the victims at East 161st Street and River Avenue last Saturday at 4:50 a.m., cops said.

The nefarious duo repeatedly punched the victim in the face, knocking him to the ground.

The punks then pounced on his gal pal, punching her in the face.

The man needed surgical staples to close a head gash, and the woman was treated for cuts and bruises.

Laureano-Rodrig and Holder were charged with gang assault and harassment, said a spokesman for DA Robert Johnson.

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Police are looking for the man pictured here, who is wanted in a violent armed robbery in Tremont.

The alleged thief, described as a 28-year-old Hispanic man, approached the victim from behind at the Grand Concourse and East 187th Street on March 22 at 8 p.m. and flashed a gun.

The thug roughed up the 24-year-old man and took unspecified property.

The goateed thief stands 5-foot-10 and weighs 170 pounds.

He also has two teardrops tattooed under his left eye.

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A tenant from hell was arrested for stabbing his building superintendent in Hunts Point, cops said.

Knife-wielding Rafael Rodriguez, 50, accosted the victim in front of the building at St. John Avenue and Southern Boulevard April 23 at 9:30 p.m., cops said.

Rodriguez was charged with assault and menacing.

Staten Island

An auto thief in Stapleton was busted after a police-car chase, authorities said yesterday.

Cops spotted John Branch Jr., 20, getting into a stolen GMC Envoy at Irving Place and Targee Street Tuesday at 7:30 p.m., sources said.

He allegedly sped off but came to a stop after hitting two parked cars.

An officer tried to pull Branch out of the vehicle, but the suspect threw it into reverse while the cop hung on, sources said.

Branch was charged with assault and resisting arrest, said a spokesman for DA Daniel Donovan.

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A hot-shot wannabe was busted after he was showing off a gun in a New Brighton deli, authorities said yesterday.

Marcellin Hyman, 19, and friends were on Jersey Street near Corson Avenue Thursday at 12:15 p.m., sources said.

Hyman allegedly had a semi-automatic visibly tucked into the waistband of his pants.

Cops were called and arrested him, while recovering the weapon and several rounds of ammunition.

Hyman was charged with weapon and ammo possession.