A Wisconsin man is behind bars after police say he brutally beat his girlfriend’s daughter, causing fatal injuries.

GazzetteXtra reports that 30-year-old Steven M. Horan is charged with first-degree reckless homicide in connection with the death of his girlfriend’s 15-month-old daughter.

According to court documents, the child’s mother left her alone with Horan, who had been drinking “throughout the day,” according to Lt. Charles Aagaard of the Janesville Police Department. When the woman arrived home, she found her daughter unresponsive with noticeable injuries on her body.

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At around 12:30 a.m. Saturday morning, the mother contacted 911. The child was taken to the Javon Bea Hospital in Rockford, Illinois, where she was pronounced brain dead. On Monday, she passed away.

Janesville Police Chief David Moore indicated that Horan was acting “emotional” when authorities arrived, although he declined to elaborate on “what kind of emotion” the suspect displayed.

Channel 3000 reports that Horan has a criminal history with previous charges of property damage, drug paraphernalia possession, and driving under the influence.

The child’s mother had been dating Horan for around three months when the incident occurred, according to police. He had previously watched the little girl on other occasions without any reported issues.

The name of the victim has not yet been released.

Horan is currently behind bars at the Rock County Jail a $10,000 cash bond.

The story is developing. Check back for updates.

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[Feature Photo: Steven Horan/Police Handout]