A Nassau County music teacher accused of killing his sister-in-law is set to face new charges.
Joseph Horner, 27, of North Massapequa will be indicted on two additional counts of murder and two counts of rape, court documents show.
As News 12 has reported, the Oceanside educator allegedly strangled his wife's 25-year-old sister, Victoria Castle, to death last month.
Prosecutors say Horner asked her to help him move a piano into his apartment, while his wife wasn’t home, and then killed her before having sex with her.
Officials tell News 12 the home on N Oak Street was multi-family and split into two apartments, where the married couple and Castle all lived.
Horner has allegedly admitted to lusting over his wife's sister for years and that day he saw an opportunity to follow through on his "sexual desire.”
He is scheduled to be arraigned on the Grand Jury indictment Wednesday morning in Mineola court.
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