A convicted drug felon in state prison is the second person to be charged in connection with the overdose death of a Donegal Township man last year.

The Pennsylvania Attorney General's Office on Monday charged William C. Thomas III, 31, with a top count of drug delivery resulting in death, the equivalent of third-degree murder under state law.

Investigators allegedly linked Thomas, formerly of Homestead, Allegheny County, to the sale of fentanyl-laced heroin that caused the death of 33-year-old Joshua Lee Stitt.

A bricklayer and father of a 5-year-old son, Stitt injected the tainted drugs at his home Sept. 16, 2015. He died in an ambulance on his way to Butler Memorial Hospital.

Toxicology tests later showed the heroin, unbeknownst to Stitt, was mixed with the synthetic painkiller fentanyl, authorities said, which is known to heighten the dangers and potency of street drugs.

State police in April arrested Julia L. Zaludek, 25, of Fenelton accusing her of selling the lethal drugs — packaged in glassine bags marked “Hit and Run”— to Stitt.

She is currently free on bail while awaiting trial on several charges, including drug delivery resulting in death, which carries a maximum sentence of 40 years in prison.

The state attorney general's office is prosecuting the case since Zaludek's mother, Bonnie Zaludek, works for the County District Attorney's Office.

And according to court documents, Zaludek is cooperating with investigators.

A month after she was arrested, during an interview with police, she identified Thomas as her “source” in obtaining heroin, documents said.

She recounted that on the day before Stitt's death, the two drove to Pittsburgh's Homestead section where she had previously arranged to meet with Thomas to buy 75 stamp bags of heroin for $400.

Accompanying Zaludek and Stitt on the alleged drug buy were both their young children as well as her boyfriend.

Following the purported drug deal, the three adults divvied up the bags.

Zaludek told police, documents said, that she knew Thomas by the nicknames “Loc” and “B.J.” She also described the tattoos on his face.

Investigators in July interviewed Thomas at the Allegheny County Jail. He acknowledged that he knew Zaludek and her boyfriend, but he denied selling or giving the couple any drugs.

He also denied going by the nicknames that Zaludek disclosed to police.

But days later in a recorded jailhouse conversation with a woman, documents said, Thomas instructed her to go to his Facebook and Instagram accounts and “take that Loc (expletive) out of my name.”

At one point during the conversation, investigators said, the woman, who was not identified, also apparently referred to Thomas as “B.J.”

Along with drug delivery resulting in Stitt's death, Thomas is charged with involuntary manslaughter, delivery and possession with intent to deliver a controlled substance, and possession of a controlled substance and drug paraphernalia.

The defendant is being held in the State Correctional Institution at Greene County. Court records show he's serving a 2- to 4-year sentence stemming from his conviction for felony drug possession at a Jan. 13 bench trial in Allegheny County.