Mohammad Bin Abdullah al-Sayf al-Jaber al-Buaynayn al-Tamimi was from the Bani Tamim tribes that are widespread in the Arabian Peninsula. His tribe was originally from Jubail in northeast Saudi Arabia. He was born in Qassim and died at the age of 37. The shakyh studied as a student of knowledge under Shaykh Muhammad bin Salih al-’Uthaymin (rahimahullah). Abu ‘Umar al-Sayf had “five brothers, two older ones, Mubarak and Ibrahim, who work at the Royal Commission in the Jubail Industrial Zone East of the Kingdom of [Saudi] Arabia, and three younger ones: Faisal, Badr and Ali, respectively. He also had six sisters. His father died while Abu ‘Umar was in college, and his mother still lives with her children in Jubail, where the whole family moved after they left Qassim”.

Abu ‘Umar al-Sayf’s brother, Ali al-Tamimi, told the al-Hayat newspaper, “my brother participated in jihad in Afghanistan. He studied with Dr. Abdullah Azzam (rahimahullah) then returned to Saudi Arabia after the Russian army’s withdrawal and the civil war broke out in Afghanistan. My brother completed his university education in the College of Sharia at Imam Muhammad Bin Saud Islamic University; upon graduation, he was offered a job opportunity in the judicial field, but he declined and joined up with the Mujahideen again”.

The shaykh went to Afghanistan in 1986 and stayed there for two years. During this time he only went back home once. Later, he returned home and graduated with honors from Imam Muhammad Bin Saud Islamic University. Abu ‘Umar al-Sayf went back to Chechnya in “1996 with his Saudi wife; two-year-old firstborn son; and two-month-old daughter, Asmaa, at the time.”

In Chechnya he join the ranks of the Arabs there when the battles against Russian forces were heating up under the leadership of the mujahid Samer as-Suwaylim (better known as Khattab - rahimahullah).

Shaykh Abu ‘Umar ascended to the position of the Mufti of the Mujahideen in Chechnya, and he exerted great efforts in spreading the knowledge between the ranks of the Mujahideen, and conducting research in various Jihad related topics, just as he exerted great efforts in reviving the concept of applying the Shari’ah in the land of Chechnya by way of training the students of knowledge and sending them to various parts of Chechnya in order to spread knowledge there and to help the people deal Islamically with their daily problems. His concerns included all Jihad arenas and were not confined to the Chechen issue alone. He also gave advises and wrote treaties regarding the jihad in the Arabian Peninsula and Iraq.

Abu ‘Umar al-Sayf, who was responsible for the Islamic courts in Chechnya when then-Chechen president, Zelimkhan Yandarbiev, attempted to declare Chechnya an Islamic state, became an ideologue of the Arab fighters in Chechnya and connected the presumed state in Chechnya with groups of Muslim clerics in the Arabian Gulf. He was one of the founders of the Mujahideen Shura Council of Sheeshaan.

Abu ‘Umar al-Sayf married a Chechen woman, who was also martyred with him in Dagestan. He had three children with his Saudi wife—the youngest a six-year-old boy he had in Chechnya when his wife was staying with him before she returned to Saudi Arabia in 1999 with all her children.

He was injured numerous times and there were several assassination attempts on his life.The Shaykh was not killed in Chechnya itself. Rather, he was martyred in the neighboring Republic of Dagestan, in mid November 2005 (1426 Hijri).

Description of his martyrdom:

Russian forces were (falsely) informed of the presence of a group of Mujahideen in a house, among them a prominent commander. The Russians brought in helicopters and heavy artillery to choke the Mujahideen out in anticipation that they would resist or try to escape. They then surrounded this house in which there was nobody except for the Shaykh - there were no other Mujahideen in the house. The Russians demanded that all in the house surrender to them; otherwise they would demolish the house and kill all who were inside. The Shaykh refused this demand and instead decided to fight. The Russians did not know that it was the Shaykh was in the house and that he was the one firing at them. Russian Special Forces then proceeded to storm the house, so the Shaykh threw an explosives belt that he was carrying at them, which resulted in many of the Russians - as well as the Shaykh himself - being killed.

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