Kenya Mall Attack Rehearsed, 'Meticulously Planned' Plus: Gunshots still ringing out By Evann Gastaldo, Newser Staff Posted Sep 25, 2013 7:50 AM CDT 9 comments Comments Kenyan soldiers run through a corridor on an upper floor, shortly after an explosion was heard, at the Westgate Mall in Nairobi, Kenya Tuesday, Sept. 24, 2013. (AP Photo/Ben Curtis) (Newser) – Some of the terrorists who attacked Kenya's Westgate Mall are said to have used G3 assault rifles, cumbersome guns carried by Kenyan security officers, and "you don't bring something like a crew-served weapon through the door," an American official tells the New York Times. "Those must have been stored well beforehand." The Times spoke to a number of American security officials, who offered an inside look at the attack—and the terrorists' preparations—based on intelligence reports, witness accounts, and intercepted electronic communications: The al-Shabab militants hid their guns in one of the mall stores days before the attack, with an employee's help, officials say. At least one also stored extra clothes; witnesses say some of the militants changed clothes, ditched their guns, and escaped with fleeing hostages after the massacre. The attack was "rehearsed," says the Times, and details as minute as the building's ventilation system were studied. During the attack, the terrorists "were not interested in hostage-taking" or negotiating, a Kenyan official tells CNN. "They only wanted to kill." They did, however, allow some Muslims to leave the mall after interviewing them at gunpoint to confirm their religion, survivors say. Meanwhile, shots were still ringing out at the mall this morning, despite the fact that Kenya's president said yesterday the siege was over, Fox News reports. A government spokesperson tells the AP the shots are from Kenyan forces who were still clearing the mall room by room, firing proactively before going in. Also: An apparently al-Shabab-linked Twitter account believed to be genuine claims the Kenyan government purposely demolished the mall, burying 137 hostages, but a government spokesman says the mall collapsed as a result of a fire the militants set Monday as a diversion, which caused structural weakness; he denies 137 people were buried and says the bodies known to be in the rubble were included in the official death toll of 61. The same Twitter account also accused the government of using "chemical gases" inside the mall, which the government spokesperson also denied.