Transcript for Westgate: Footage Shows Brutal Nairobi Mall Massacre
Now, to a new terror threat. The u.S. Government warning an attack like the one on the kenyan mall that left dozens dead, could be on the verge of happening again. This comes as horrifying new video from inside that mall massacre is released. And abc's brian ross is here with the latest on that story. Good morning. Reporter: Good morning, elizabeth. This new video obtained by abc news, is so chilling because of the casual, callous way the gunmen went about their saturday morning massacre, at a popular shopping mall. Reporter: First, there is the panic, as shoppers realize what is happening. Then, the heavily-armed gunmen, strolling through. Picking off victims, one by one, including this security guard, cowering in fear. The shoppers scramble for cover, as the four gunmen take control of the mall. At one point, talking on cell phones, presumably to commanders outside the mall. Later, a mother is seen calmly leaving the supermarket. And behind them, a wounded teenager, followed by one of the gunmen. She and the mother and the children, all escaped safely. I think they knew they had a soft target. They knew the authorities would not respond quickly. Reporter: Leaving enough time for the gunmen to stop the killing and take turns praying. They had hours virtually to meander around the mall and shoot people. Reporter: U.S. Officials believe the men behind the attack were part of an al qaeda-connected group based in somalia. Now, the u.S. Has issued a new warning to americans that the group may be planning a similar style attack. This one in the african country of uganda. We put out the statement because of information available. Because of the specificity of that, I'm not going to outline that. Reporter: The new video is being screened by authorities to answer a number of lingering questions. Security experts continue to be amazed that the four men could hold off kenyan police and army forces for almost four full days. In fact, the fbi is now screening news video taken of shoppers fleeing the mall to see if any other attackers were able to slip out during the panic and now could be part of the planning for yet another mall massacre. Elizabeth? Brian, thank you so much.
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