The father of a 3-month-old baby who died Sunday has been charged with the infant's killing, Allegheny County police said.

Michael Lewis, 54, first was treated for a drug overdose before he was arrested this afternoon on homicide charges in the death of his son, DeCarlo Lewis.

Medics were summoned at 6:58 p.m. Sunday to Mr. Lewis' apartment in the 1900 block of Hyer Avenue, where they found Mr. Lewis in the throes of an overdose from an undisclosed drug, county homicide detectives said.

Police also found the baby unresponsive and not breathing at the time.

The boy was taken to UPMC McKeesport, where he was pronounced dead at 7:41 p.m., the county medical examiner said.

He died of head trauma.

The medical examiner and police ruled the death a homicide.

Mr. Lewis also was taken to UPMC McKeesport where he was treated, police said.

He was awaiting arraignment this afternoon on charges of homicide, child endangerment and resisting arrest.

The father and son lived at the apartment with the boy's mother, whose name was not released.

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