Bomb 'meant to explode on plane

The bomb found on a plane in the UK was designed to go
off on the aircraft, the British PM says, as Yemen arrests
a woman suspected of involvement. Plot shows bombers' ambition
Cameron phones US, Yemeni leaders Q&A: Cargo plane bomb plot
In pictures: Plane bomb plot Device 'meant to explode on plane
(source: http://www.bbc.co.uk/news/)