British police are believed to have recovered "martyrdom" videotapes for each of the eight people who were charged today with conspiracy to murder in the alleged plot to blow up U.S.-bound aircraft, according to sources familiar with the case. Three others were charged with less serious offenses, and 11 others remain in custody for further investigation. The BBC reported last week that the tapes were recovered on computers seized during a series of searches. The tapes were recorded by the alleged suicide bombers with the apparent intention they be played after the attacks had been carried out. British police said today they had seized bomb-making equipment and more than 400 computers in 69 searches carried out in the last 10 days.