Terri A. Reed, 34, of Woodstock.

A homeless woman was charged with mailing a letter containing a white powdery substance to the Woodstock Police Department, prompting a hazardous materials response earlier this month.

Terri A. Reed, 34, who is listed as a transient from Woodstock, was charged with one count of disorderly conduct, a Class 3 felony.

Woodstock Police Department Detective Sergeant Joshua Fourdyce said a police records clerk opened a letter addressed to the Woodstock Police Department around 10 a.m. on August 9.

A white powdery substance was released into the air and onto the skin of the records clerk.

The Woodstock Fire and Rescue District along with a hazmat team was dispatched to the Woodstock Police Department.

Fire crews evaluated the records clerk who opened the envelope and others who were in the room when the envelope was opened, Fourdyce said.

The envelope also contained paperwork and other items. Those items and additional evidence were used to identify Reed as the suspect.

The United States Postal Inspection Service and the Federal Bureau of Investigations (FBI) also assisted in the investigation.

The powder was determined to be a medication that is not harmful to human life, Fourdyce said.

The McHenry County State’s Attorney’s Office approved the felony charge against Reed and an arrest warrant was obtained on Tuesday, court records show.

Fourdyce said the warrant was served on Reed, who was already in custody at the McHenry County Jail for an unrelated case.