Afghan intelligence officials said today that they have broken up a cell which was plotting to kill President Hamid Karzai, arresting six people in Kabul whom they claimed were affiliated with al-Qaida and the Haqqani militant group.

America has said it is “inconceivable” that Osama bin Laden did not have a support system in Pakistan which enabled him to remain in the country for long periods.

America and its allies were today braced for violent reprisals from al-Qaida after Osama bin Laden was killed in a dramatic raid by US special forces.

The discovery of Osama bin Laden’s hideaway in a city at the heart of Pakistan’s military establishment today revived questions about alleged links between al-Qaida and elements in the country’s security forces.