May 26, 1962 - An explosion of unknown origin caused a Continental Airlines jetliner to disintegrate in flight and crash in the vicinity of Centerville, Iowa, last Tuesday night, a Civil Aeronautics Board spokesman said today. All 45 persons aboard were killed in the crash. In Denver, Robert F. Six, Continental’s president, asked the F.B.I. to enter the investigation because, he said, the airline had “sufficient evidence to indicate the probability that a man-made explosive had been set off within the aircraft.” The Chicago office of the F.B.I. confirmed that its agents were investigating the case but refused to comment on the inquiry. There have been unconfirmed reports that insurance totaling $225,000 had been taken out on one passenger in Chicago. Investigators have determined that an explosion occurred in the rear portion of the fuselage.