Houston, TX – A Harris County sheriff’s sergeant is in the hospital on Tuesday night after she was exposed to a substance believed to be Fentanyl, on a flyer that was left on the windshield of her patrol vehicle.

Tuesday afternoon, the Harris County Sheriff’s Office held a press briefing to warn the public to watch out for the paper flyers.

Harris County Sheriff Ed Gonzalez said that the flyer the sergeant touched had also been placed under the windshield wipers on about a dozen additional sheriff’s department vehicles parked on the street in front of the sheriff’s office’s recruitment and criminal investigations center on Lockwood Drive in East Houston, The Houston Chronicle reported.

“We hope this is an isolated incident,” Sheriff Gonzalez said.

Investigators said they were not positive the sheriff’s department fleet vehicles were targeted, since they were unmarked and parked on a city street, and said they wanted to warn the general public to be wary of anything found on their windshields.

However, the text on the flyers was addressed to “FBI, Police, Firemen” and contained information on conspiracy theories about the government targeting individuals with subliminal messages from cell phone towers.

The sergeant who was affected came into contact with the opioid-laced paper as she left work on Tuesday afternoon, according to KTRK.

She started to feel woozy as she drove, so she pulled over and called for help.

The sheriff said she felt light-headed and exhibited Fentanyl-related symptoms, The Houston Chronicle reported.

“She caught it quickly,” Sheriff Gonzalez said. “We do know from our experience with fentanyl is that it can be very deadly. It’s 100 times more potent than morphine.”

The sergeant was rushed to the hospital and is expected to survive.

At least one of the flyers left on the cars’ windshields tested positive for Fentanyl, and the sheriff’s department was continuing to investigate.

Authorities have asked that anyone who encounters the flyers or anything similar to contact the police, The Houston Chronicle reported.