Abubakar Shekau

Abu Mohammed Abubakar bin Mohammad al-Sheikawi (also known by the alias "Darul Akeem wa Zamunda Tawheed", or "Darul Tawheed"; "the abode of monotheism"; born 1965, 1969 or 1975) is a Kanuri man known as the current leader of Boko Haram, a Nigerian Islamist militant group. He served as deputy leader to the group's founder, Mohammed Yusuf, until Yusuf was executed in 2009. 
Nigerian authorities believed that Shekau was killed in 2009 during clashes between security forces and Boko Haram until July 2010, when Shekau appeared in a video claiming leadership of the group. He has subsequently been regularly reported dead and is thought to use body doubles. In March 2015, Shekau pledged allegiance to ISIL leader Abu Bakr al-Baghdadi. Shekau is a Salafi, until 2016, when he ended his relation to ISIL; the two groups were however allies until 2021, when they becamed enemies and ISIL gunmen tried to assassinate Shekau. He has been described as possessing a photographic memory.
Biography.
Early years.
Shekau was born in Shekau town, in Tarmuwa local government, Yobe state; his exact date of birth is unknown but is said to be between 1965 and 1975. Shekau is an ethnic Kanuri, and also speaks Hausa, Fulani, Arabic, and English. In 1990 he moved to the Mafoni area in Maiduguri and studied under a traditional cleric before entering the Borno College of Legal and Islamic Studies (now called Mohammed Goni College of Legal and Islamic Studies). Shekau left the college for ideological reasons and without earning a degree. He later met Mohammed Yusuf, the founder of Jamaat Ahlus Sunnah li Dawah wal Jihad, and became one of his deputies. Shekau was appointed the leader of the group in July 2009, after the death of Yusuf in the 2009 Boko Haram uprising. Shekau survived being shot in the leg during the 2009 attempt on his life by Nigerian security forces. He is married to one of Muhammad Yusuf's four widows. His nickname is “Darul Tawheed”, which translates as "specialist in tawheed", the Islamic concept of oneness of Allah.
Leader of 'Boko Haram'.
Shekau's leadership has not gone unchallenged. He received a letter from al-Qaeda in the Islamic Maghreb giving him advice but he did not heed it. As a result of his erratic leadership, in 2012 a faction of the group broke off to form Jamaat Ansar al-Muslimin fi Bilād as-Sudn (Ansaru). This faction included his military commander Abu Muhammad al-Bauchawi, and religious advisor Sheikh Abu Osama al-Ansari Muhammad Awal al-Gombawi. Despite this, many soldiers and commanders stayed with Shekau, including military commanders Abu Sa'ad al-Bamawi and Muhammad Salafi. With his group mostly intact, Shekau engaged in conflict with Ansaru, killing their leader Abu Osama al-Ansari. As a result of this, and other arrests of Ansaru leaders by the Nigerian government, Ansaru did not pose a further threat to Shekau's leadership of the jihadi movement in Nigeria, and the group became defunct by 2015.
Shekau's fellow jihadist fighters were undisciplined and abused the populations they encountered, resulting in the establishment of civilian militias such as the Civilian Joint Task Force to fight them. Shekau is also thought to have killed his own religious advisors, including Sheikh Abd al-Malek al-Ansari al-Kadunawi and Abu al-Abbas al-Bankiwani.
In June 2012, the United States Department of State designated Shekau as a terrorist and effectively froze his assets in the United States. Since June 2013, the Department has had a standing reward of US$7 million for information leading to Shekau's capture through its Rewards for Justice program. In addition, the Nigerian army has offered a ₦50 million reward (approximately US$300,000) for Shekau.
In videos Shekau posted online, he boasted often about his invincibility; mocked various armies; and stated that he "cannot be stopped" and "cannot die except by the will of Allah". He has also boasted of being in possession of armoured tanks and other combat vehicles. His online videos frequently depict anti-American rhetoric, and he has made multiple threats to attack the U.S.
In one prominent incident, he took credit for the kidnapping of over 200 school girls in April 2014. Shekau also announced that the kidnapped girls have been converted to Islam. He has claimed to be waging a jihad against Christianity.
With the rise of the Islamic State in Iraq and Syria during 2014 and 2015, Shekau faced pressure from his commanders and soldiers to pledge his allegiance to IS leader Abu Bakr al-Baghdadi. A history of the group says that Shekau "was compelled to give allegiance, and that was through a coming together of the military commanders, and after he became convinced that the matter was about to go out of his hand, and that his throne would be shaken and emptied of him if he did not give allegiance".
In August 2016, ISIL appointed Abu Musab al-Barnawi as the leader of the group in place of Shekau. Shekau refused to recognise Barnawi's authority and split off part of the group under its original name of Jamaat Ahlus Sunnah li Dawah wal Jihad, while Barnawi lead the Islamic State's West African province. While Shekau continues to lead his group, he has only 1,500 soldiers, whereas Barnawi has 3,500. Shekau has been widely denounced as following the ideology of the Khawarij by the Islamic State and West Africa province in Nigeria.
Following the split, many clashes occurred between Shekau and Barnawi's soldiers throughout the month of August and the following months. On 12 September 2016, 30 of Shekau's soldiers were killed and 40 captured by IS-West Africa. In October 2016, Shekau's soldiers attacked the Karino area south of Lake Chad with 350 men seizing the village of Tunubuma. Then Barnawi's soldiers counter-attacked, killing more than 75, including the leader Muhammad Bakr.
Reports of death.
Shekau was reported killed in 2009 but reappeared as the group leader less than a year later. The Nigerian army in mid-August 2013 stated that he was fatally wounded when soldiers raided a base of Boko Haram in Sambisa forest and had died between 25 July and 3 August. However, a video in September 2013 was released in which a man purported to be Shekau claimed he had not been killed. The Nigerian army also stated to have killed him during the 2014 Battle of Kodunga that lasted from September 12 to 14th. The Cameroonian military posted a photo and also claimed that their forces killed Shekau in September 2014. In response to these reports, security analyst Ryan Cummings commented, "Is this his fourth or fifth death? He dies more often than an iPhone battery." In early October 2014, a video was obtained by AFP news agency that showed Shekau alive, in which he mocked the Nigerian military's allegations that he had been killed.
Chadian President, Idriss Déby claimed in mid-August 2015 that Shekau had been replaced by Mahamat Daoud without exactly specifying his fate. An audio message attributed to Shekau was released a few days later, in which he purportedly stated that he had neither been killed nor ousted as chief of the group.
Shekau was reported to have been "fatally wounded" during an airstrike in Taye village on 19 August 2016 by Nigerian Air Force which also killed some senior leaders of Boko Haram. On 25 September, a video of a man purported to be Shekau was released on YouTube, in which he claimed that he was alive and in good health.
On 27 June 2017, Shekau released a video in which he claimed responsibility for the abduction of Nigerian policewomen and criticized the Nigerian government for claiming that Boko Haram had been defeated. This video would seem to be further evidence of Shekau's continued survival. In February 2020, Shekau released a video threatening the minister of information and digital economy, Isa Ali Pantami, and making reference to what was done to Islamic scholar Ja'afar Mahmud Adam in Maiduguri when he preached against Boko Haram.
On 20 May 2021, Nigerian intelligence officials claimed that Shekau was killed or critically injured after detonating explosives in his house to avoid capture from the rival IS–West African Province faction. His fate is however unknown.