Steven Nitschke, 33, was found dead in his Stroudsburg home in March, and his cause of death was ruled fentanyl toxicity in his autopsy, said the Monroe County District Attorney's Office.
County detectives claim Nitschke got the drugs from his 39-year-old coworker Edwin Burgos, who allegedly said it was heroin.
Burgos' whereabouts are unknown to police, but he is thought to frequent the East Stroudsburg area near the Eagle Valley Shopping Center, authorities said.
He is 5-foot-9 and 210 pounds with black hair and brown eyes, and may also go by "Edwin Morales," they added.
Anyone with information is asked to call Monroe County Detective Kim Lippincott at 570-460-9600 or email klippincott@monroecountypa.gov.
If you or a loved one are struggling with substance abuse, help is available through the Carbon-Monroe-Pike Drug and Alcohol Commission at 866-824-3578.
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