Denver library temporarily closed after powerful narcotic found inside

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DENVER — A Denver library was temporarily closed after firefighters found a substance that preliminary testing identified as xylazine, a powerful veterinary tranquilizer that is not approved for human use.

The Denver Department of Public Safety said 911 was called around 11 a.m. Wednesday, Sept. 30, for a person who became sick inside the library. The person was taken to a local hospital with non-life-threatening injuries.

Courtesy: Denver Department of Public Safety

Several hours later, around 1 p.m., authorities said library staff contacted 911 after becoming concerned that a room inside the library may have been exposed to a hazardous substance connected to the earlier medical incident.

Denver firefighters returned to the library and began a Level I HAZMAT investigation. Preliminary testing detected a powerful narcotics-related substance that is not approved for human use or consumption.

The Denver Fire Department said the substance was preliminarily identified as xylazine. The veterinary tranquilizer has increasingly been found mixed with fentanyl in recent years, creating a dangerous combination associated with overdoses.

Because of the positive test and the earlier medical incident, the incident commander upgraded the response to a Level II HAZMAT response.

The Denver Police Department closed several nearby streets while firefighters established a command post and safety perimeter.

Specialized HAZMAT crews entered the evacuated library wearing self-contained breathing apparatus to conduct additional testing and evaluation. The Denver Department of Public Safety said air and surface testing found no additional risk to public safety.

Firefighters safely secured the drug, and officials from the Denver Department of Public Health and Environment took custody of it for off-site disposal.

The library remained closed Thursday and is expected to reopen Friday. No additional patients or injuries were reported.

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