Prosecutors added a new count against a man already charged in relation to a fatal overdose two months ago in Adams Township: drug delivery resulting in death.

Eugene J. Smith III, 47, of Butler Township was initially charged with, and subsequently ordered to stand trial for, felony drug possession and related counts.

But on Friday, in a motion filed in Butler County Court, prosecutors added the new charge — the equivalent of third-degree murder in Pennsylvania.

The decision to file the additional charge, said Ben Simon, a county assistant district attorney, followed toxicology results in the death of 24-year-old Elizabeth Arblaster of Brady Township.

The findings, included in a pathologist’s report released Wednesday, showed that Arblaster died Sept. 3 of fentanyl and heroin toxicity.

Police suspect Smith on Sept. 2 sold Arblaster stamp bags containing the highly toxic combination.

Fentanyl is a synthetic opioid painkiller that is similar to morphine but 50 to 100 times more powerful, drug abuse experts say.

Simon said the pathologist’s report indicated Arblaster had nine times the lethal level of fentanyl in her system when she was found dead in the bedroom of a home on Stoup Road in Adams Township that she had been visiting.

Several stamp bags of heroin, some marked “The King,” investigators said, as well as syringes and a cooking spoon were found in the bedroom.

Smith’s name came up quickly during the joint investigation by Adams Township police and the Butler County Drug Task Force.

A search of Arblaster’s cell phone showed text messages between her and Smith, authorities said.

Arblaster’s boyfriend, also admitted taking her to the defendant’s home at the Old Plank Estates apartment complex in Butler Township, where she allegedly bought the suspected fentanyl-tainted heroin.

“According to the pathologist,” Simon said Friday, “7 nanograms of fentanyl would kill you. (Arblaster’s) blood showed she had a level of 63 nanograms.”

Police and narcotics officers, armed with a search warrant, raided Smith’s apartment Sept. 8.

Inside the home, investigators said, was evidence of a drug-dealing operation — dozens of bags of heroin and crack cocaine, owe sheets and more than $1,600.

Seized in a back bedroom was a plastic bag containing 20 glassine bags of heroin marked “The King.”

Police believe Michael D. Burrows, 30, of Wilmerding, Allegheny County, had been using that bedroom while staying at Smith’s apartment.

Both men were at the apartment and arrested during the raid. They both were also charged with felony and misdemeanor drug possession and conspiracy.

Additionally, Burrows was subsequently charged with having a stolen gun, which turned up during the Sept. 8 search. A felon, he also is prohibited under state law from possessing any firearms.

District Judge Kevin O’Donnell at a Sept. 22 preliminary hearing ordered Smith and Burrows held for court on all those charges.

\Simon cited “evidentiary issues” for prosecutors’ decision to seek the additional charge of drug delivery resulting in death against Smith and not Burrows. He would not elaborate.

Smith’s preliminary hearing on the new charge, a first-degree felony that carries a maximum sentence of 40 years in prison, has not been scheduled.

His attorney, public defender Joe Smith, no relation, did not return a telephone call seeking comment.

Eugene Smith was freed from Butler County Prison on $25,000 bail on Sept. 22. Burrows remains jailed on $50,000 bail.

---- Prosecutors have also asked the court to modify Smith’s bail, which could land him back in prison.