Core of al-Qaide 'essentially gone'

A year after the US Navy SEAL raid that killed Osama bin Laden, the al Qaida that carried out the September 11 attacks is essentially gone, but its affiliates remain a threat to America, anti-terror officials say.

Al Qaida’s new leader, Ayman al-Zawahri, still aspires to attack the US, but his Pakistan-based group is scrambling to survive, under fire from CIA drone strikes and lying low for fear of another US raid. That has lessened the threat of another complex attack like a nuclear dirty bomb or a biological weapon, the officials say.