At least nine people were killed Sept. 21 in an attack at the upscale Westgate shopping mall in Nairobi, witnesses said, AP and Reuters reported. Gunmen reportedly used hand grenades and opened fire with AK-47s after besieging the building. Nairobi's police chief said the attackers were trying to rob a shop inside the mall. The mall is reportedly frequented by affluent Kenyans and expatriates. Grenades were used in several attacks in Nairobi in 2012.