July 7 London bombings
Al Jazeera has aired two video tapes by Al Qaida on Thursday evening. In one of them, the terror group's second in command Ayman al-Zawahiri has claimed responsibility for the 
 and threatened further attacks. The alleged leader of the London bombers, Mohammad Sidique Khan, appeared on a separate recording and outlined his reasons for the bombings.
Al-Qaida claims responsibility for London 7/7 bombings