Kirkersville Police Chief Steven Eric DiSario died from a shotgun wound outside the nursing home. Medrano reportedly got several civil protection orders against Hartless who had a history of domestic violence.
The Newark Advocate reported sheriff's deputies and investigators from the Ohio Bureau of Criminal investigation took the guns from the home of 43-year-old Thomas Hartless hours after the shooting at a Kirkersville nursing home.
A search warrant was executed at his home on Oakland Avenue in Utica.
Medrado also reportedly told police that Hartless had previously showed her to a hole he had dug, and said he would put her in it if she ever left him. That case was under review May 12, for the filing of formal charges, when Hartless killed her and the others. Hartless used a shotgun and a handgun to kill ex-girlfriend Medrano, authorities say.More news: Trump administration issues formal call to renegotiate NAFTA
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He promises it won't be a whitewash - he said, "Mistakes were made over here", and "it's important for the families and the public to understand what happened".
According to court and police records, Hartless had stayed at Medrano's home as recently as eight days before the shooting. He admitted in court that beat up the woman, even that he tried to run over her with his vehicle as she tried to run from him.
"I am not trying to validate why he acted the way he did", she wrote.
Funerals are scheduled Friday for Medrano and Saturday for DiSario. Cindy Krantz, a nurse's aide, was shot and killed with a shotgun.