The emergency room entrance is seen at Eastern Idaho Regional Medical Center in Idaho Falls.

The Idaho Falls Police Department is investigating an incident in which a patient entered Eastern Idaho Regional Medical Center with a container of what appeared to be fentanyl.

According to a joint statement from EIRMC and the Idaho Falls Fire Department, a patient entered the hospital with a container of the substance, telling doctors they had ingested some.

The hospital isolated the patient and doctors who had contact with them until the substance was identified.

The substance was sent to a lab to confirm it was fentanyl. According to Idaho Fire Department Public Information Officer Kerry Hammon, the substance was mixed with olive oil. The mixture had a volume of 7.5 milliliters.

“The cap on the container was not opened until the hazmat team conducted testing of the substance, and this testing was done in a controlled environment. Air quality testing was also conducted by the hazmat team and was deemed negative, indicating that there was no threat of airborne contamination,” Hammon wrote in an email.

Idaho Falls Police Department spokeswoman Jessica Clements said the investigation is ongoing.

According to the Drug Enforcement Agency, fentanyl is “a synthetic opioid 80-100 times stronger than morphine.”

Under Idaho law, fentanyl is classified as a schedule II substance, with some compounds classified as schedule I substances.