itself and announceed it will respond to congressional demands for detailed explanation of u.s. objectives in libya. today, a rebel spokesman said thousands of troops loyal to muammar gaddafi are advancing on rebel-held misurata. tripoli, nato airstrike hit the gaddafi scrolling come pound and military targets again. while libya's ultimate fate may be settled on the ground, dan springer shows us that rebels are also patrolling the sea. >> just outside benghazi, the latest recruit train for battle. all member of the new navy. >> i joined the navy to defend ourself against killing troops of gaddafi. >> the rebel navy has taken on the role of coast guard patrolling the shoreline. here they nag down a small fishing boat. they are looking for explosive, weapons and pro-gaddafi fighters. >> we do patrols and we expect anything can happen from