725 ILCS 165/1

When a complaint is made to any circuit court that a person possessing a firearm or firearms has threatened to use a firearm illegally, the court shall examine on oath such complainant, and any witnesses which may be produced, reduce the complaint to writing and have it subscribed and sworn to by the complainant. If the court is satisfied that there is any danger of such illegal use of firearms, it shall issue a warrant requiring the apprehension of such person, hereafter referred to as the defendant, for appearance before the court. Such warrant shall also authorize the seizure of any firearm in the possession of the defendant.