Five-year-old Kenny Kreuscher was visiting family in Montana on March 5 whenhe was shot dead by his mother, 41-year-old Sara Atkinson, in his sleep.

Kreuscher says he broke up with his wife a few years ago, and since then they had shared custody of their son.

Recently, Kreuscher says his ex had stopped taking medications and was becoming increasingly paranoid, believing there were cameras and bombs hidden away in her home. She also became violent towards their son, Kreuscher claims. In one video - recorded just days before his son's death - Ken speaks to Kenny about a bruise on his arm allegedly caused by the boy's mother. 'She punched me like that,' Kenny says in the clip.'Who punched you?' his dad asks. 'Mommy,' the boy responds.

Kreuscher says he showed the video to a case worker, who came to visit his home shortly after. However, the case worker reportedly told the concerned father that there wasn't much she could do.  'And she stood in front of me and pointed at my closet and said, "Unless your kid's being stuck in a closet every day or beaten every day, I'm not going to do anything about it, and if you call back, if I hear back from you about this kind of stuff, I'm going to take him from you and her,"' Kreuscher toldKDVR. Kreuscher says he tried in vain to get a restraining order against his ex and that she even threatened to kill their son before. 'She had threatened to do it before,' Kreuscher told KUSA. 'She said, "I'm going to kill myself. I'm going to take him with me."'

Denver child protection authorities released astatement following the boy's death, adding that they can't release many details on the situation as of now.