Crime Okla. Man Allegedly Threw Toddler Against Wall, Killing Him, Because He Wouldn't Go to Sleep Zachary Collins, 24, has been charged with child abuse murder By Harriet Sokmensuer Published on December 13, 2017 04:48 PM Share Tweet Pin Email Photo: Tulsa County Jail An Oklahoma man is behind bars after he allegedly slammed his girlfriend’s toddler into a wall, killing the boy, PEOPLE confirms. Zachary Collins, 24, has been charged with child abuse murder, Corporal Mark Kraft of the Tulsa Police Department’s Child Crisis Unit tells PEOPLE. Collins initially faced charges of child abuse and neglect after his Saturday arrest. However, after the boy died Monday morning, the charges were upgraded to child abuse murder, Kraft tells PEOPLE. The boy has not been identified by authorities. On Saturday, Tulsa police responded to a call regarding an unresponsive child. Upon officers’ arrival, Collins told them the boy had been pushed off the couch by his older sibling. During police questioning, Collins later allegedly admitted to beating the child after becoming upset with him, Kraft says. • Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter. Collins allegedly told police that on Friday night, he babysat three of his girlfriend’s young children while she worked the graveyard shift. (Collins is the father of the two other children left in his care, Kraft says. He is not the victim’s father.) During the night, the 22-month-old child would not fall asleep, Collins told police, according to Kraft. Collins allegedly admitted to slamming the toddler’s head into the wall, with an impact so severe it left a hole in the wall. He also allegedly admitted to punching the child’s stomach and throwing him onto the couch until he was unconscious, says Kraft. When the child’s mother returned home Saturday morning, she discovered her son unresponsive and had relatives call police, Kraft says. Collins allegedly admitted to taking drugs and drinking alcohol while babysitting the children, Kraft says. • For more compelling True Crime coverage, follow our Crime magazine on Flipboard The child was taken to a local hospital where he remained unresponsive until his death Monday morning, according to Kraft. Hours before the incident, Collins appeared in court on a separate domestic violence charge, Kraft tells PEOPLE. It is unclear whether he has entered a plea to those allegations or retained an attorney. Collins is schedule to appear in court on murder charges Tuesday. It was not immediately clear if he has retained an attorney or entered a plea to the child abuse murder charge against him. He remains behind bars on $500,000 bond for the murder charge, according to jail records. No additional arrests have been made in the toddler’s death, however, Kraft says detectives are continuing to investigate.