Osama Bin Laden: Top of Washington's 'Most Wanted' list
Since the 11 September 2001 attacks, a number of video tapes, audio recordings, faxes and other statements have been attributed to Osama Bin Laden.
But although the US has hunted the al-Qaeda leader using satellite tracking systems and sophisticated spying systems, Bin Laden remains at large.
He is widely believed to be hiding in the remote tribal region along the Pakistan-Afghanistan border with his deputy, Ayman al-Zawahri. US officials insist his capture remains a top priority.
A Taliban detainee in Pakistan tells the BBC he met a trusted contact in January or February of 2009 who had just come from a meeting with Osama Bin Laden.
The detainee said his contact, a Mehsud tribesman, had come from Ghazni in Afghanistan. "I think that's where the Sheikh was," he said.
The BBC's Orla Guerin, who interviewed him, says his account suits Pakistan, which maintains that Bin Laden is not on its soil, although the British and US think otherwise.
However, former CIA analyst Bruce Riedel says his story is plausible, and is an important new lead and should be investigated.
A US Senate report says American forces had Bin Laden "within their grasp" in Afghanistan in 2001.
It said Bin Laden and his bodyguards "walked unmolested out of Tora Bora and disappeared into Pakistan's unregulated tribal area".
"Failure to finish the job" laid the foundation for "today's protracted Afghan insurgency and inflaming the internal strife now endangering Pakistan," the report, prepared by the Foreign Relations Committee Democratic staff, says.
It rebuffs claims by the Bush administration at the time that intelligence about Bin Laden's location was inconclusive.
An audio message purported to be from Bin Laden accuses US President Barack Obama of fuelling hatred of the US in Pakistan, blaming American pressure for the Pakistan army's crackdown on militants in its Swat Valley region.
The tape is aired by al-Jazeera as Mr Obama arrives in Bin Laden's Saudi Arabia for a brief visit at the start of a Middle East tour, which sees him make a keynote speech to the Muslim world in Cairo.
CIA director Michael Hayden says Osama Bin Laden is probably hiding in the tribal area of north-west Pakistan and is "putting a lot of energy into his own survival". He says Bin Laden appears to be isolated from the day-to-day operations of al-Qaeda, but that the organisation is still the greatest threat to the US.
Bin Laden appears in a 30-minute video posted on an Islamist website - his first video appearance in three years. The video is undated, but in it, Bin Laden makes reference to recently elected leaders such as French President Nicolas Sarkozy and British Prime Minister Gordon Brown.
The broadcast comes days before the sixth anniversary of the 9/11 attacks, and Bin Laden urges the US public to embrace Islam "in order to stop the war in Iraq".
Afghan warlord Gulbuddin Hekmatyar says his fighters helped Bin Laden escape a US assault on the Tora Bora mountains in late 2001. In the rare interview with Pakistan's private Geo TV network, he said they helped the al-Qaeda leaders "out of the caves and led them to a safe place".
In his fourth audio message of the year, Osama Bin Laden praises Abu Musab al-Zarqawi, the leader of al-Qaeda in Iraq who was killed three weeks earlier. The 19-minute message, posted on an Islamist website, shows a still picture of Bin Laden and moving pictures of Zarqawi.
In an audio tape attributed to Osama Bin Laden, the speaker cites the cutting of Western funding to the Hamas-led Palestinian government as proof of a "Zionist-crusader war against Islam".
Western involvement in the troubled Darfur region of Sudan is also criticised in the tape, aired by Arabic TV station al-Jazeera.
After a silence of more than a year, al-Jazeera aired an audio tape which CIA analysts say was made by Osama Bin Laden.
In it, the speaker said new attacks on the US were being planned, but offered a "long-term truce" to the Americans, an offer the US quickly rejected.
Pakistan's President Pervez Musharraf says Pakistani troops had their best chance of capturing Bin Laden from May-July 2004, after the army launched an offensive along the border with Afghanistan. But he says the trail has now gone cold.
In the US, President George W Bush makes a rare mention of Bin Laden, saying the US is "working day and night" to bring him to justice.
An audio tape attributed to Osama Bin Laden calls on Iraqis to boycott January's election.
The voice, whose identity cannot be confirmed, names the Jordanian-born Abu Musab al-Zarqawi as "emir" of al-Qaeda in Iraq.
A Bin Laden videotape surfaces just days before the US presidential election.
In the tape, aired on the Arabic television station al-Jazeera, Bin Laden says the reasons behind the 9/11 attacks are still present and he threatens fresh attacks on the US, whoever is elected.
It is Bin Laden's clearest claim of responsibility so far for the 2001 attacks.
In an embarrassment for the Pakistani president, al-Jazeera says the tape was delivered to its Islamabad bureau.
Al-Jazeera releases an audio tape in which Bin Laden talks about the capture of Saddam Hussein and attacks Arab states for backing the US-led war on Iraq.
In audio tapes aired by al-Jazeera television station, Bin Laden praises the 11 September hijackers and calls for new attacks on the US.
An audio recording said to be of Bin Laden, in which he calls for attacks on the governments of the Gulf states, is released by the Associated Press news agency.
Senior al-Qaeda leader Khalid Sheikh Mohammed is arrested in Pakistan. Investigators believe he kept in contact with Bin Laden through e-mails and hand-delivered messages.
An audio tape purporting to be from Bin Laden calls for attacks on US and British targets if Iraq is attacked. The US-led invasion of Iraq takes place the following month.
In a tape broadcast on Arabic TV station al-Jazeera, Bin Laden refers to attacks in Bali, Yemen and the Moscow theatre siege which had recently taken place.
An alleged planner of the 11 September attacks, Ramzi Binalshibh, is captured in the Pakistani city of Karachi.
Old clips of Bin Laden and some of his top aides are aired on al-Jazeera, along with footage of an 11 September hijacker reading what appears to be his suicide note.
US forces apparently intercept radio messages in which Bin Laden is directing troops from Afghanistan's mountainous region of Tora Bora, but the trail goes cold and US officials admit they have no information on the al-Qaeda leader's whereabouts.
Meanwhile, al-Jazeera television airs footage of Bin Laden in which he refers to the attacks.
A letter said to be from Bin Laden calls on Muslims in Pakistan to stand up for Islam as the country supports the US-led campaign against Afghanistan.
Bin Laden warns in a statement - broadcast on al-Jazeera two hours after the US-led coalition begins military strikes against Afghanistan - that it will have no rest until the Middle East conflict is resolved and US military bases in the region are shut down.