Key developments in the long hunt for Al-Qaeda leader Osama bin Laden:
- 1991: After participating in the guerrilla war that successfully forced Soviet troops out of Afghanistan, a campaign backed by the United States, bin Laden turns against both the US and his home country, Saudi Arabia. He objects in particular to the basing of US troops in the kingdom during the Gulf War.
- 1996: Sudan, from where bin Laden has been providing support for Islamic extremist groups in countries such as Algeria and Egypt, expels him under pressure from several countries, including the United States. He and his Al-Qaeda group reappear in Afghanistan, which has fallen to the fundamentalist Taliban.
- 1998: After the devastating bomb attacks against US embassies in Kenya and Tanzania, east Africa, an American court indicts bin Laden in absentia for the murder of US citizens.
- 2001: The attacks of September 11 on the United States put bin Laden's name at the top of "most wanted" lists around the world.
US president George W. Bush calls for the Saudi fugitive to be taken "dead or alive", and his country offers a $25 million reward for information leading to his capture.
By December, a US-led force has invaded Afghanistan, toppled the Taliban regime and attacked the remote mountains in which bin Laden is believed to be hiding. But they fail to capture him.
- 2002: A new video shows bin Laden alive, although it is impossible to confirm when it was filmed.
- 2002-5: Pakistan captures a series of militants believed to be close to bin Laden, including his close confidant Abu Zubaydah, and Khalid Sheikh Mohammed, who is believed to have organised the September 11 attacks.
- 2003: The United States leads an invasion of Iraq, which it accuses of making weapons of mass destruction and also, according to several US officials, of having helped Al-Qaeda.
- 2004: Pakistan begins a military operation to tackle suspected Al-Qaeda fighters in a region near the Afghan border where bin Laden and his deputy, Ayman al-Zawahiri, are thought to be hiding. But they are not captured.
- 2005: Pakistan says its intelligence services have lost track of bin Laden for almost a year. Separately, Afghan President Hamid Karzai says the fugitive is not in Afghanistan.
- 2006: Then US intelligence chief John Negroponte says bin Laden is believed to be operating in the Afghan-Pakistan border area.
Five years after the September 11 attacks, the US Congress appropriates $200 million for a special unit to track down and catch bin Laden.
However the French intelligence services report that according to the Saudis, the elusive militant has died of typhoid fever in Pakistan..
- 2007: Six years after the September 11 attacks, bin Laden is shown in a video in which he praises one of the militants who carried out the suicide attacks.
- July, 2009: A US counterterrorism official says that one of bin Laden's sons may have been killed by an American missile strike on Pakistan earlier in the year.
- 2010: Pakistani Prime Minister Yousuf Raza Gilani says that bin Laden is not in his country.
CIA chief Leon Panetta says bin Laden is very well hidden and protested in a tribal region of Pakistan.
May 1, 2011: US President Barack Obama says that the United States has killed bin laden and recovered his body during a commando operation at Abbottabad, a city just north of Islamabad.