HARRISBURG — A Pennsylvania doctor who prescribed nearly 3 million doses of opioids during a recent 19-month period has been charged with causing the overdose deaths of five people, federal prosecutors said Thursday.

The U.S. attorney’s office in Harrisburg said Dr. Raymond Kraynak, 60, of Mount Carmel, was indicted on five counts of drug delivery resulting in death, 12 counts of unlawful distribution of a controlled substance and two counts of using his doctor’s offices as “drug-involved premises.”

Prosecutors said a state monitoring program identified Kraynak as having issued the most opioid prescriptions of any physician in Pennsylvania over the 19 months that ended in July.

Authorities did not disclose the names of the five patients but said they died between 2013 and 2015.

A federal public defender who represents Kraynak said he hopes to be released on bail so he can help his patients obtain treatment.

“At this point, we haven’t received any discovery, so I really don’t know exactly what’s going on here,” said the defense lawyer, Tom Thornton. “Our greatest concern is for Dr. Kraynak’s patients who still need treatment, they need care.”

The U.S. attorney’s office said Kraynak prescribed about 2.8 million dosage units of opioids to about 2,800 patients over the 19-month period. They accused him of issuing prescriptions without conducting proper medical exams, verifying his patients’ medical problems or assessing their risk of drug abuse.