BATON ROUGE — A woman accused of selling drugs to a man who later overdosed has been arrested by East Baton Rouge Parish deputies on murder charges.

According to deputies, a man overdosed on July 2. In the man's pocket, deputies found two suspect Xanax pills inside of a clear plastic bag and a pill bottle containing a plastic straw and a plastic bag with white powder. 

Coroner investigators conducted a presumptive toxicology test, which showed positive results for fentanyl, THC, opioids, TCA and barbiturates. A more comprehensive coroner's report identified fentanyl overdose as his cause of death.

The 27 ng/mL of fentanyl in his blood was within the concentration range of 9.7 and 41.3 ng/mL typically found in overdoses, the coroner's report pointed out.

There were no initial signs of foul play, but it was later determined that, one day before his death, 27-year-old Montronnik Johnson sold the man drugs, including heroin and fentanyl, which were both found in his system. 

A review of Johnson's phone records, as well as a scan of her license plate the day the drugs were sold, placed her near the man's home before his overdose death.

Johnson was arrested on Tuesday on one count of second-degree murder. 

WBRZ has asked authorities to identify the man killed in the overdose.