HACKENSACK - A Teaneck man pleaded not guilty today in the murders of his girlfriend and her five-year-old daughter.

Michael Brady, of Teaneck, entered his plea today at New Jersey Superior Court in Hackensack. He's accused of fatally stabbing Tammy Pitts-Gaddy then using a plastic bag to smother her five-year-old daughter, Natasia Gaddy.

Brady has been charged Wednesday with murder, hindering apprehension and weapons charges.

According to police, Brady had been in a dating relationship with Pitts-Gaddy for the past three years. The two lived together at her Englewood home intermittently during their relationship. Natasia was not his biological daughter.

The Bergen County Prosecutor's Office says Brady and Pitts-Gaddy had an argument on the day of the murders. Police believe Natasia witnessed her mother's violent murder before Brady then killed the child.

A judge declined to reduce Brady's $2 million bail.

AP wires contributed to this report.