MI5 chief quits as full story of July 7 is about to emerge

The head of MI5 has resigned weeks before full details of the role of her agents in a surveillance operation involving two of the July 7 bombers are due to be revealed.

Dame Eliza Manningham-Buller, whose organisation has been at the forefront of the war on terror, is leaving after more than four years as director general.

[See liquid bomber plot story below]