Cops yesterday solved one mystery surrounding a gun found in the trash near the scene of a triple homicide on the Upper West Side: It’s definitely the murder weapon.
But they don’t know how it got there.
Gunman Hector Quinones fell out of a window to his death while trying to escape after shooting and stabbing three men Thursday in an Amsterdam Avenue apartment where cops later found a heroin stash.
Detectives initially believed that a .380-caliber Hi-Point semiautomatic pistol recovered in the apartment was the murder weapon. But ballistics later showed it wasn’t.
Investigators then found the .380 Beretta Saturday in a trash can bolted to the side of the building, matching it to the crime.
Cops said they believe that Quinones acted alone but that a passer-by might have picked the Beretta up off the ground after the perp dropped or tossed it as he fell and hid it in the garbage in hopes of retrieving it for his own purposes.