§ 133.02  REFUSING TO AID AN OFFICER.
   No person, upon command, shall refuse or knowingly reasonably fail to aid a person known by him to be a police officer in:
   (A)   Apprehending a person whom the officer is authorized to apprehend; or
   (B)   Preventing the commission by another of any offense.
(ILCS Ch. 720, Act 5, § 31-8)  Penalty, see § 130.99