OAK LAWN, Ill. — A father in Oak Lawn is now charged with first-degree murder after authorities say he admitted to shaking his 8-week-old infant, eventually leading to the child’s death.

Cook County State’s Attorney approved a first-degree murder for Edward Janiszewski. An autopsy concluded that the child’s death was ruled a homicide due to injuries consistent with child abuse.

Janiszewski was initially charged with aggravated battery to a child and released on bail. Janiszewski was taken back into custody Wednesday and will appear in bond court on Thursday.

On June 2, police responded to Hope Children’s Hospital for a report of an infant with severe head and brain trauma. Upon arrival, staff told police that the child had initially been seen on May 27, with what was thought to be a stomach illness and dehydration.

According to officials, the child was in and out of the hospital over the next several days. On May 30, the baby was brought back to the hospital and was unresponsive, police said.

Hospital staff notified the Child Abuse Team and diagnosed the child with severe head and brain trauma, consistent with a shaken baby.

The infant died days later, on June 5.

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According to police, Janiszewski admitted that he shook the infant and slammed the baby’s head on a cushion on May 30.