The latest U.S. intelligence suggests that the crash of Metrojet Flight 9268 was most likely caused by a bomb on the plane planted by ISIS or an ISIS affiliate, according to a U.S. official familiar with the matter.<br />The official stressed that there has not been a formal conclusion reached by the U.S. intelligence community.<br />"There is a definite feeling it was an explosive device planted in luggage or somewhere on the plane," the official told CNN's Barbara Starr.<br />The assessment was reached, the official said, by looking back at intelligence reports that had been gathered before Saturday's plane crash and intelligence gathered since then.<br />The United States did not have credible or verified intelligence of a specific threat prior to the crash, however, the official said, prior to the incident, "there had been additional activity in Sinai that had caught our attention."<br />Another U.S. official said the intelligence regarding ISIS is in part based on monitoring of internal messages of the terrorist group.<br />Those messages are separate from public ISIS claims of responsibility, that official said.
