Saudi Arabia acts to shut down a large Islamic charity that the US alleges has offered funding to al-Qaeda. The move blocked the passage of money to the al-Haramain Islamic Foundationís branches in Somalia and Bosnia.
President George W Bush orders an investigation into the mailing of visa approval notices to two of the alleged 11 September attackers six months after they are believed to have died in the attacks. A flight school in Florida received letters from the Immigration and Naturalization Services, awarding student visas to Mohammed Atta, the alleged ringleader of the attackers, and compatriot Marwan al-Shehhi.
CIA chief George Tenet says Iraq has had contact with al-Qaeda, may be working with the group and has a long history of supporting terrorism. American advocates of "regime change" in Iraq seize on this.
Abu Zubaydah was arrested in Pakistan
American forces capture a high-ranking al-Qaeda official, Abu Zubaydah, during a raid on a house in Pakistan. American officials say Abu Zubaydah is co-operating with them, and he is believed to have given several leads about possible terror attacks in the US.