English: Augusta Bay, Sicily (Apr. 22, 2004) - Italian Special Forces personnel board an Italian SH-3 helicopter of the Reparto Eliassalto during exercise Clever Sentinel 2004. The exercise is a multilateral maritime interdiction training exercise led by Italy in the Mediterranean Sea. The exercise was part of the U.S. launched Proliferation Security Initiative (PSI), a collaborative effort to take active measures against trafficking in WMD, their delivery systems and related materials to and from states and non-state actors of proliferation concern around the world. Five nations, including the U.S., provided assets for the exercise and several nations sent observers to the exercise. U.S. Navy photo by Journalist 3rd Class Stephen P. Weaver. (RELEASED)