Blood stained the ground at the scene today in Khost, where a suicide bomber struck. Anwarullah /Reuters /Landov hide caption

itoggle caption Anwarullah /Reuters /Landov

A suicide bomber struck a convoy of buses today in Kabul, killing at least 12 people — mostly foreigners. Massoud Hossaini /AFP/Getty Images hide caption

itoggle caption Massoud Hossaini /AFP/Getty Images