According to a document entitled “Terrorism Awareness and Prevention: Participant Guide” distributed by the New Jersey Office of Homeland Security & Preparedness (which you can see embedded below), almost every single action should be treated as suspicious. These include glances, wide open eyes, cold penetrating stares, trance-like gazes, exaggerated yawning when engaged in conversation, protruding or beating neck arteries, repetitive touching of face, tugging on or covering ears, increased breathing rate, panting, excessive fidgeting, clock watching, head turning, pacing or jumpiness, trembling, unusual perspiration, goose bumps, and/or rigid posture with minimal body movements and arms close to sides.

http://theintelhub.com/2012/03/22/homeland-security-pretty-much-all-bodily-movement-is-an-indicator-of-potential-terrorism/