The mother of a New Cassel woman allegedly killed by her ex-boyfriend spoke exclusively to News 12 Long Island Tuesday about the lawsuit she plans to file against police.

Sharon Dorsett says her daughter?s death could have been prevented. Twenty-four-year-old Joanna Bird, a mother of two, was stabbed to death March 19, allegedly by her ex-boyfriend. Bird?s family members say they called 911 repeatedly just before the murder to report that the suspect, Leonardo Valdez-Cruz, was harassing her. When police arrived, the family says officers refused to go inside as relatives pleaded with them to help.

?I said ?Please my daughter's in the house, please kick the door open, please, she could be in there bleeding, she could be hurt, she's not responding,? and they said, ?No, we can't,?? Dorsett says.

Dorsett says Valdez-Cruz had threatened to kill Bird several times, but the officers were unhelpful and unsympathetic. When they finally went inside, Bird was bleeding heavily from multiple knife wounds, the mother says.

Bird?s family members say the police failed their loved one. Their attorney, Fred Brewington, says Bird?s autopsy results back up the family?s allegations.

?They did nothing, they stood outside, they cracked jokes, they prevented family members from trying to rescue this young lady, and as a result she died a very horrible death,? Brewington says.

Nassau police declined to comment on the story. Bird's family plans to formally announce the lawsuit Wednesday morning.