1 atom bomb is lost !

BBC found that after a plane accident in 1968 they lost a atom bomb in Grönland under a ice block. In that plane there was 4 bombs and that plaine exploded after this accident they found 3 of theese bombs but they couldn't find one of them. USA told that they had explode all of thoose bombs but BBC insist that they send an submarine and it also couldn't find.