And, now, we turn here to our coverage of the middle east, and here is what's happening tonight. The protests spread. There are now 51 u.S. Kons lalts and embassies and they are warning u.S. Citizens... See More
And, now, we turn here to our coverage of the middle east, and here is what's happening tonight. The protests spread. There are now 51 u.S. Kons lalts and embassies and they are warning u.S. Citizens to be extra vigilant. Our team is covering all the angles and abc's lama hasan starts us off in the streets of cairo today. Reporter: Tonight, diane, even at this late hour, the protests are not letting up. It has been a day of rage aimed squarely at the u.S. Security forces defending the embassy, hitting hard, firing tear gas, forcing them away. Protesters pushing forward -- throwing back tear gas canisters. A crowd so inflamed with anger, this is as close as we can get to the u.S. Embassy. The egyptian army has just arrived outside the building. Police won't let us go anywhere near it and even from where we are standing, you can hear the security forces firing volley after volley of tear gas. There's definitely a feeling that a crackdown is about to begin. 1,300 miles away in yemen, demonstrators climbed over a metal fence surrounding the u.S. Embassy. They poured through the compound, breaking windows. Frightening scenes, but officials say the protestors did not breach more critical security inside the compound images of anger directed at america seen over and over again. Iraq, iran, afghanistan and pakistan. Fueling this fury that online movilled "the innocence of muslims," which denigrates the prophet muhammad. It was produced in america. In cairo, people in the streets telling us that the american government is to blame. We asked them what they want america to do. They want an official apology from president obama. On twitter, a spat broke out between the u.S. Embassy and the ruling egyptian political party the muslim brotherhood. The embassy warning the brotherhood that it was reading -- in arabic -- tweets sent from their account -- supporting the protesters. "By the way, have you checked out your own arabic feed? I hope you know, we read those, too." Tomorrow, the muslim brotherhood is calling for a peaceful march. But diane, we know the demonstrations are unpredicta unpredictable. The city is on edge. Thank you so much, lama. Now, we turn to that tragedy in libya. We learned more today about those five hours under siege in the dark of night, ending in the death of u.S. Ambassador chris stevens and three other americans. There have been arrests in libya tonight. We have two reports. We'll start with abc's jeffrey kofman on the ground. Jeffrey? Reporter: Good evening, diane. At least one of the militants believed to be involved in that attack that killed the u.S. Ambassador and three others has been arrested. That according to libya's new prime minister that is determined to show he's cooperating with the united states. He sails more arrests will follow. Meanwhile, two u.S. Destroyers have been positioned off the coast of libya and an elite team of 50 u.S. Marines has arrived here to guard the u.S. Embassy and to assess security. Nonessential personnel have been evacuated to germany. The mood here on the streets, calm but tense. Ople here coming up to us, saying, please tell the people in america we are so sorry. Now, let's turn to my colleague, martha raddatz, with more on what we are learning about security that night. Reporter: Jeffrey, this new view of the consulate where that five-hour attack raged shows few signs of security before the attack. The small guard shack just inside the compound easily breached. Cutting a clear path to the main building where two americans were killed, while two others were in the house used as a safe haven. It's where some of the employees had taken refuge during the attack. We now know that inside that battle, a former navy s.E.A.L. We did evaluate the threat stream and determined that the security was appropriate for what we knew. Reporter: But just the day before the attack, there were warning signs. Al qaeda's lead earl urging libyans to retaliate against americans for the death of a libyan-born militant. And the state department was aware that that anti-muslim movie was airing on egyptian tv. Yet, there were no warnings about it to other u.S. Missions. Why there weren't warnings about the movie. Why they assumed that is a big question, given that whenever there has been anything denigrating mo hall made has
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