Just in: An ISIS letter has claimed responsibility for the brazen assault on 60 passengers in a bus in Karachi today. Six to eight gunmen wearing police uniforms attacked a bus carrying Shia Ismaili community members and shot the passengers in the head, killing at least 47 people in Pakistan's southern port city of Karachi. The letter has threatened more attacks will follow.


Image: The ISIS pamphlet claiming responsibility for the Karachi attack. Click on the picture for a larger image.