BOSTON -- A 7-year-old boy died Tuesday from injuries suffered when he was beaten by his father, according to the Worcester County District Attorney's Office.

“This has turned from a case of severe physical abuse to a murder investigation,” said Tim Connolly, spokesman for Worcester District Attorney Joseph D. Early Jr. told the Boston Herald late Tuesday.

Leslie G. Schuler, 36, and his girlfriend, Tiffany Hyman, 28, both of Worcester, were arraigned Tuesday in Central District Court on a series of charges in connection with the alleged beating of Nathaniel Turner, 7.

"He's on life support. Tests are being done to determine levels of brain activity. The physicians are very concerned about the child's ultimate prognosis," prosecutor Paula Frasso said before the boy's death on Tuesday.

The boy was removed from life-support on Tuesday afternoon and he died, the paper reported.

Schuler took the unconscious and unresponsive boy to St. Vincent's Hospital on Sunday with bruises on his face and torso. Officials said it appeared the abuse had been ongoing for several weeks.

"The injuries noted by the doctor include multiple and substantial bruises to the left side of his chest; his face was bruised and he had multiple bruises on the left side of his body including his face, forehead, eye, ear, arm, forearm, elbow and leg," Frasso said.

Frasso added, "belts, hand slapping ultimately ended up on Father's Day with an assault and the child vomiting and the child being unresponsive."

Schuler was charged with four counts of assault and battery on a child with injuries, three counts of assault and battery on a child causing serious bodily injuries, assault to murder and two counts of assault with a dangerous weapon. He was held on $250,000 bail.

There is no evidence that Hyman ever laid a hand on Nathaniel, but because she never stopped the alleged abuse, which her attorney called "disciplining," Hyman and Schuler both face assault charges, which could soon be upgraded to murder.

Schuler, Hyman and Nathaniel shared a small townhouse on Arline Street, where neighbors said they rarely saw Schuler and Nathaniel, but what they did see, they didn't like.

"This dad (was) yelling at the kid, snatching him by the shirt, telling him not to play outside with the other kids," said Cynthia De Reda, a neighbor.

Hyman was charged with two counts of assault and battery on a child causing serious bodily injuries. She was held on $50,000 bail. Her defense attorney said she never hit the boy.

It was not immediately clear if additional charges would be filed now that the boy has died of his injuries.

"He is precious and we are as devastated as everyone else," Bruchetta Swindell, Hyman's sister, said of Nathaniel.

Until about two months ago and for much of his life, Nathaniel lived with his grandmother in Alabama, but under a court order, the boy was allowed to visit his dad in Worcester.