Prosecutors are expected to bring murder charges against a Worcester man accused of fatally beating his 7-year-old son on Father's Day.

Nathaniel Turner was removed from a ventilator early Saturday morning at UMass Memorial Medical Center.

The boy was declared brain dead Tuesday after his father, Leslie Schuler, allegedly slammed his head against a wall so hard that it left a dent inside Schuler's Worcester home.

The 36-year-old Schuler and his live-in girlfriend, 28-year-old Tiffany Hyman have pleaded not guilty to assault and battery charges.

Prosecutors said they were conducting a murder investigation after the boy's dearth. Police said it appears Hyman did not strike the boy but could have intervened and stopped the abuse.

Nathaniel had been living with his father since Memorial Day.

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