>> indeed. barbara starr reports there can concerns troyer groups could exploit the chaos. >> reporter: yemen now on the brink of civil war. amid the rising unrest, the united nations warninging the worst may to be come as a group -- as groups apply for power. >> unless a solution can be found in the coming days the country will slide into conflict and fragmentation. >> reporter: a u.s. official tells cnn al qaeda fighters which have vowed to attack the u.s. are moving quick three increase recruiting and continue plotting attacks. the u.s. just became essentially blind on the ground. more than 100 u.s. military commandos like these who'd been tracking al qaeda known as aqap secretly ordered out of the country by the pentagon over the weekend. the special operations forces were evacuated by military