Al-Qaeda around the world
Al-Qaeda, the Islamist militant network once led by Osama Bin Laden, may have underground cells in dozens of countries, but its main areas of activity, and those of some of its affiliates, are detailed below.
Afghanistan and Pakistan
Al-Qaeda was originally set up in Peshawar in 1988, and the tribal areas of the Afghanistan-Pakistan border region remain the front line in the war against Islamist militants.
Al-Qaeda's co-operation with the Taliban meant that Osama Bin Laden was given sanctuary in Afghanistan prior to the September 11 attacks on New York and Washington.
Having left Afghanistan in 2001, as a result of the US invasion, Bin Laden was ultimately found and killed in Abbottabad, Pakistan, in 2011.
Ayman al-Zawahiri, last seen in Afghanistan in October 2001, was named the new leader of al-Qaeda in June 2011.
The US has stepped up its programme of drone strikes against suspected al-Qaeda leaders in regions along Afghanistan and Pakistan's shared border under President Barack Obama - a strategy which, its supporters believe, has been effective in taking leading militants "off the battlefield".
Allies of al-Qaeda in Pakistan include Lashkar-e-Jhangvi and Lashkar-e-Taiba, who are alleged to have helped hide senior al-Qaeda figures.
Lashkar-e-Taiba founder Hafiz Mohammad Saeed helped Bin Laden set up al-Qaeda in 1988. His group was responsible for the 2008 Mumbai attacks, which killed 174 people.
The Haqqani network and other Pakistani Taliban groups are also allies of al-Qaeda, as is the Islamic Movement of Uzbekistan (IMU). Like al-Qaeda, it found sanctuary in Pakistan's border areas after the US invasion of Afghanistan in 2001.
Al-Qaeda in the Arabian Peninsula (AQAP) was formed in January 2009 by a merger between two regional offshoots of the international Islamist militant network in Yemen and Saudi Arabia.
The group has vowed to attack oil facilities, foreigners and security forces as it seeks to topple the Saudi monarchy and Yemeni government, and establish an Islamic caliphate.
AQAP members have been linked to an attempt to blow up a Detroit-bound passenger jet in December 2009, parcel bombs found on cargo planes in October 2010, and what was believed to be a further foiled attempt to bomb a US-bound passenger plane in May 2012.
A key figure in AQAP, the radical American Muslim cleric Anwar al-Awlaki, was killed in a US drone strike in September 2011.
A jihadist insurgent group was formed in Iraq in 2003 in opposition to US-led invasion, and its leaders declared allegiance to Osama Bin Laden's network in October 2004.
Al-Qaeda in Iraq - also known as al-Qaeda of Jihad Organisation in the Land of the Two Rivers (Mesopotamia) - has been behind attacks which have killed and injured thousands of people over the past 10 years.
Violence in Iraq peaked in 2006-7, as al-Qaeda in Iraq and other Sunni groups that joined the Islamic State of Iraq umbrella organisation, targeted security forces and Shia civilians. Shia militants meanwhile launched deadly reprisal attacks.
Al-Qaeda in Iraq's capacity began to diminish in 2008, when Sunni Arab tribesmen turned on it and the US military launched a troop "surge".
However, the group remained active and in 2013 a wave of sectarian violence has swept Iraq, leaving thousands dead. The Islamic State of Iraq has been blamed for dozens of attacks on Shia districts.
It also claimed responsibility for two mass jailbreaks in July 2013, which freed hundreds of prisoners including prominent militants.
In the chaos of Syria's civil war, jihadist militant groups have come to the fore.
There is a struggle within the armed uprising against President Bashar al-Assad between moderates and radical Islamists linked to al-Qaeda.
Ayman al-Zawahiri has urged al-Qaeda fighters to strive for an Islamic state in the country.
However, the al-Nusra Front rejected the merger - though still pledged its allegiance to al-Qaeda.
Al-Qaeda has long been active in East Africa, the scene of the attacks on the US embassies in Nairobi, Kenya and Dar es Salaam, Tanzania in August 1998.
Those attacks were carried out by fighters from Egypt, Sudan, Kenya, Tanzania, Comoros and Saudi Arabia. Some had undergone training in Somalia, where they fled afterwards.
Al-Shabab said it was behind the twin suicide bombings which killed 76 people in Uganda's capital Kampala in July 2010. It claimed the attacks were revenge for Uganda's decision to send peacekeeping troops to Somalia.
Despite being pushed out of key Somali cities since 20111, al-Shabab still remains in control of smaller towns and large swathes of the countryside.
North and West Africa
The vast desert spaces of the Sahara and the Sahel provide militant groups with the ideal terrain to flex their muscles.
AQIM has its routes in the Algerian civil war of the 1990s.
Originally known as the Salafist Group for Preaching and Combat (GSPC), it aligned itself with Osama Bin Laden, and then changed its name in 2007. The leader of the group is Abou Mossab Abdelwadoud.
In May 2013, suicide bombers attacked a military barracks and a French-run uranium mining site in the north of Niger.
France sent troops into Mali in January 2013 to drive out Islamist militants from the northern cities of Timbuktu, Kidal and Gao.
Al Qaeda's presence in Europe is not as structured as elsewhere. Counter-terrorism officials describe militants here as inspired by al-Qaeda, but not always directed by them.
The attackers who killed 52 people in London on 7 July 2005 are believed to have had al-Qaeda links.
A major plot to bring down airliners using fertiliser bombs was foiled in 2006, and five men were convicted the following year.
Recent months have seen further convictions of British-born men for planning violence in the UK, including a plot to bomb an English Defence League rally and an "attack to rival the 7 July and 9/11 atrocities".
In April 2011 German police arrested three suspected al-Qaeda members whom they believed posed an imminent threat.
Other threats were uncovered in Europe in September 2010, when Western intelligence sources said they had disrupted a plot to seize and kill hostages in the UK, France and Germany.
Responsibility for the Madrid train bombings of March 2004, which killed nearly 200 people, was claimed by groups with links to al-Qaeda.
The al-Qaeda cell blamed for 9/11 was based in Hamburg. A mosque frequented by the 9/11 plotters was eventually closed in 2010, because it was allegedly still hosting extremists.
In this region, two groups thought to have links to al-Qaeda are based in Indonesia and the Philippines.
Jemaah Islamiah, based in Indonesia, is believed to have been responsible for the attacks on nightclubs in Bali in 2002, which killed over 200 people.
Other targets of the group, whose history goes back to the 1980s, have included Christians in eastern Indonesia and the tourist industry.
The Abu Sayyaf group, based in the southern Philippines, is said by the United Sates to have links with the al-Qaeda network. Involved in multiple kidnaps for ransom, its main aim is for an independent Islamic state in Mindanao and the Sulu islands.