Was the Afghan Bomb Attack an Inside Job?

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" (CBS) It all happened at a well-fortified combat outpost in Eastern Afghanistan. Somehow a suicide bomber was able to bring his explosives on the base, walk up to a group of American civilians and blow himself up. It will take an investigation to determine how he did it.

But the outpost is located in the middle of a notorious stronghold for Afghan insurgents near the border with Pakistan, reports CBS News correspondent David Martin. "