UPDATE: An Oceanside music teacher has been charged with murdering his sister-in-law, whom prosecutors say he strangled. Joseph Horner, 27, of North Massapequa, pleaded not guilty in the killing of the 25-year-old woman, who was found not breathing by police in a ground-floor apartment attached to a home in North Massapequa. A Nassau ADA said Horner, who lives in an upstairs apartment at the home, asked the victim for help moving a piano and "without warning and unprovoked" then attacked her from behind and placed her in a chokehold "until her body went limp." Read the latest updates on this story at the link in bio. . . . #longisland #liny #nassau #nassaupolice #crime