MINEOLA, N.Y. — A New York man has been sentenced to life without parole for killing his estranged girlfriend after tormenting her for months.

Leonardo Valdez-Cruz was convicted in April of first-degree murder and other charges in the death of Jo’Anna Bird. He was sentenced Monday in Nassau County Court.

Prosecutors say Valdez-Cruz defied an order of protection and terrorized the 24-year-old mother of two for several months. He broke into her Long Island apartment in March 2009 and stabbed her to death.

Seven Nassau County police officers were disciplined for not fully investigating Bird’s domestic violence calls in the days before she was killed.

Caldez-Cruz insisted to reporters outside the courthouse on Monday that he was innocent.