The Kremlin said for the first time on Tuesday that a bomb did bring down a Russian passenger plane that crashed over the Sinai Peninsula in Egypt on Oct. 31, killing all 224 people on board. 'One can unequivocally say that it was a terrorist act,' Alexander Bortnikov, the head of Russia's FSB security service, told a meeting chaired by President Vladimir Putin, according to a transcript published on the Kremlin's web site.