HARRIS COUNTY (CBSDFW.COM) – Flyers laced with the opioid Fentanyl were found on windshields of Harris County Sheriff’s Office vehicles in east Houston on Tuesday. One sergeant received medical treatment after coming in contact with one of the flyers.

The flyers were found Tuesday afternoon on some sheriff’s vehicles, according to a tweet from authorities. Anyone that sees the flyers anywhere are urged to call authorities and to not touch them.

Authorities say the sergeant who came into contact with the Fentanyl-laced flyer is alert and receiving treatment.

Fentanyl is an opioid commonly used to treat severe pain. It can be deadly in high doses.