covered activity
(2) Covered activity The term “covered activity” means any suspicious transaction, activity, or occurrence that involves, or is directed against, a passenger transportation system or vehicle or its passengers indicating that an individual may be engaging, or preparing to engage, in a violation of law relating to— (A) a threat to a passenger transportation system or passenger safety or security; or (B) an act of terrorism (as that term is defined in section 3077 of title 18 ).