happening now, a deadly day of anti-u.s. rage across the muslim world. we're monitoring events that have u.s. security officials extremely concerned right now. president obama leads the mourners as the bodies of the u.s. ambassador and others killed in libya return to the united states. and mitt romney ramps up his criticism of the president again as the latest polls show him falling behind in several crucial states. i'm wolf blitzer. you're in "the situation room." >>> but we begin with these live pictures. look at this. this is tahrir square in cairo. these are live pictures coming in not far from the united states embassy. once again, the protests escalating even as we speak. earlier in the day it had been relatively -- keyword,