A Pennsylvania woman was charged with criminal homicide for the death of her 11-week-old son after an autopsy showed the baby had died because of drugs in the mother’s breast milk, prosecutors said.

Samantha Jones, 30, had been prescribed methadone to help her overcome her addiction to painkillers, and took it during pregnancy and after giving birth, according to a statement from Buck’s County District Attorney’s Office dated July 13.

An autopsy found the baby died April 2 from a combination of methadone, amphetamine and methamphetamine transmitted through Jones’ breast milk, according to the charging documents.

Jones’ attorney Louis Busico said the baby’s death was not intentional, according to the district attorney’s office statement.

Busico was not immediately available for further comment at his law office in Newtown, Pennsylvania on Monday.

Jones is the latest in a series of U.S. mothers charged for the deaths of their infant children after they breastfed them having previously taken methamphetamine, a stimulant used by more than 12 million people in the United States, according to the government-run National Institute on Drug Abuse.

Use of methamphetamine during pregnancy can lead to increased rates of premature delivery for the child as well as heart and brain abnormalities, among other problems, the institute said on its website.

Jones said she had been primarily breast-feeding the baby, but had switched to formula three days earlier, saying the infant was not getting enough milk from breast feeding, the documents said.

Jones told police that after her husband left for work, she fed the baby the formula, placed him in a bassinet at about 6:30, and fell asleep. She awakened an hour later to find the infant pale, with bloody mucous coming from his nose, the documents said.

Jones began CPR at the instruction of a 911 dispatcher. The child was taken to hospital where he was pronounced dead.

Bail was set at $3 million cash and a preliminary hearing is scheduled for Aug. 29, the district attorney’s office said.

(Reporting by Andrew Hay in New Mexico; editing by Diane Craft)