The attackers –&nbsp;members of the Somali Islamist extremist group al-Shabaab – spent weeks reconnoitering the site. They knew every exit and safe haven, and they appear to have leased a shop where they pre-positioned ammunition, explosives, and heavy weaponry.
局面之复杂让调查者大吃一惊。袭击者——索马里伊斯兰极端组织青年军（al-Shabaab）花了数周时间踩点。他们请出每一个出口和安全站，他们似乎还租了一个店面用来预先放好枪支、炸药和重型武器。他们对社交媒体的使用也可以成为数字营销的经典案例。