The Black Lives Matter and NYC Shut It Down groups joined family members of a slain mentally ill woman to demand consequences for the police officer who shot her.

Dozens of protesters marched Wednesday night in support of Deborah Danner, 66, who police say an NYPD sergeant fatally shot Tuesday while responding to a 911 call at a Pugsley Avenue apartment in Castle Hill. They took their rally to the NYPD's 43rd Precinct.

According to police, Danner was inside her apartment and armed with scissors. Police Sgt. Hugh Barry, an eight-year veteran of the force, told Danner to put down the scissors and walk out of the room. She picked up a bat and attempted to swing it at Barry, who shot her twice in the stomach. 

She later died at Jacobi Medical Center, police said.

Jennifer Danner, the victim's sister, said she believes police did not follow the proper procedure for handling a mentally ill person.

"I want to make it very clear that the New York City Police Department has once again failed to properly respond to dealing with mentally ill patients without resorting to deadly physical force," she said.

Jennifer Danner called on Bronx District Attorney Darcel Clark, state Attorney General Eric Schneiderman and United States Attorney General Loretta Lynch to fully investigate the slaying.

Mayor Bill de Blasio called the shooting "tragic and unacceptable."

Police Commissioner James O'Neil told the press "we failed." He said police should only use deadly force in dire situations and ought to protect life.

Wallace Cooke Jr., a cousin of Danner who is also a retired police officer, said he would have handled the situation differently. He said his cousin had schizophrenia and may have been off of her medication at the time of the shooting.

Community members are also criticizing the shooting.

Carlton Berkley, a retired NYPD detective, told News 12 that he does not think the officer should have opened fire.

"What he was supposed to do is isolate, contain, and let emergency service come," Berkley said. "I've encountered many emotionally disturbed people, and I have never had to fire my firearm."

"For anyone that has a mental illness...it's difficult for them," said Daniel Porro, a member of Community Board 9. "Our system cannot treat them fast enough or appropriately."

Barry has been placed on modified assignment.

City law officials say he was once previously investigated in connection with alleged police brutality. That was settled for $25,000.