LONDON, Aug 10 (SPA) - The key figures in a plot to blowup several passenger planes flying between Britain and theUnited States are now in custody, Home Secretary (interiorminister) John Reid said on Thursday. "The police are confident that the main players have beenaccounted for," Reid told a news conference, adding theoperation was ongoing and further arrests might be made. Police are holding 21 people in connection with the plot,which Reid said would have caused "a loss of life to innocentcivilians ... on an unprecedented scale". The suspects were seized in overnight raids in London,southeast England and Britain's second city Birmingham, Reuters reported.--SPA www.spa.gov.sa/381973