Early evidence in the December 30 bombing that killed seven CIA agents suggests a link to Pakistan, two senior Afghan sources, including an official at their spy agency, told The Daily Beast. The pair said that U.S. has already taken a chemical fingerprint of the bomb used by a Jordanian double agent in the attack, and that it matches an explosive type used by their Pakistan equivalents, the Directorate for Inter-Services Intelligence, or ISI. The bomb’s provenance was an immediate concern after the attack, which took place in a remote base in eastern Afghanistan called Camp Chapman, because of its...