BALTIMORE (WJZ) — The mother of two young girls allegedly killed by their father—former Baltimore County Police officer Robert Vicosa—filed a complaint against the police chief in York, Pennsylvania.

She claims the chief stopped enforcement of a protective order she filed against her estranged husband after he brutally assaulted her and fled with the kids. Police are also investigating whether there was a delay of almost 24 hours between her assault complaint and police arriving at her home to investigate.

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The chief has yet to respond to the allegations, but the district attorney there did. He has referred them to the Pennsylvania Attorney General.

“I cannot and will not discuss any further details regarding the private criminal complaint or any specific facts related to these allegations,” said D.A. David Sunday. “On even the best days and circumstances, law enforcement cannot prevent every instance of evil or thwart every plan,” Sunday said at a press briefing.

Police believe Vicosa shot the girls, along with his accomplice, Baltimore County Police Sergeant Tia Bynum, and then himself. It happened seconds after Pennsylvania State police activated lights and sirens to pull them over in Western Maryland.

In her first interview since the deaths, Baltimore County’s Police Chief Melissa Hyatt talked to WJZ Investigator Mike Hellgren about the response. “There was a point in time that we attempted contact with Tia Bynum: Anything we could do with the hope of bringing those children home and bringing them home safely. Unfortunately, we were not successful.”

Hyatt also talked about the impact on the department. “This tragedy does not define the Baltimore County police department or the brave heroes who work here every day,” Hyatt said. “As we continue to move through this tragedy, internally supporting our employees in the best way we can, we remain committed to working with our partners on the investigation with this case.”

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Robert Vicosa’s mother told WJZ her son was on medication for depression at the time of the killings.

“The little grandbabies, they were the daughters that I always wanted, and I loved them. And they were goood babies. And they were loved babies,” Beverly Brown said. “My baby snapped and killed himself and his babies. This mental health is real. It’s like high blood pressure. It’s a silent killer because of stigma. People think if you suffer from depression or PTSD that makes you crazy. You’re not crazy. You just need some counseling, maybe medication, maybe therapy, but you’re not crazy.”

She said she has personally been threatened. “I wouldn’t wish what I’m going through on any mother. My heart is so heavy right now.” Vicosa’s mother also recounted the last time she had contact with her son the day before the murder-suicide “My son wanted to know was Sgt. Bynum ok. I told him I didn’t know, but my mother did. I gave him the phone and he spoke to my mother for a minute and that’s the last time I heard from my son.”

Maryland State Police are still investigating the circumstances surrounding the murder-suicide.

Robert Vicosa had been fired from his job in the Baltimore County Police Department in August.

“In addition to the discrimination and depression, he found himself facing administrative charges that he claimed were trumped up—and he ended up losing his job behind it,” said J. Wyndal Gordon, an attorney for Vicosa’s mother. “Obviously, that sent his depression into a downward spiral. He was trying to manage his depression by going to therapy and taking medication, but when he lost his job, all things came crumbling down. And this is not an excuse for his conduct, but it’s an explanation.”

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