WHEATON – A letter containing an unknown, powdery substance was received by the DuPage County Circuit Clerk's Office on Monday, prompting an investigation by the DuPage County Sheriff's Office, according to a sheriff's office news release.
The letter was received at about 1:15 p.m. at the DuPage County Courthouse, 505 N. County Farm Road, the release said. An employee who opened it found the substance inside, along with the correspondence.
The clerk notified deputies assigned to the courthouse and the Wheaton Fire Department responded, according to the release.
Preliminary tests by the department, the DuPage County Sheriff's HAZMAT personnel and the FBI Chicago office determined the substance was not harmful, the release said.
The investigation is ongoing.
The sheriff's office did not immediately return calls for comment.
DuPage County State's Attorney's Office spokesman Paul Darrah declined to comment pending the continuing investigation.