(RFE/RL) -- Muhammad Yusuf was a self-proclaimed Islamic scholar who led a militant group called Boko Haram.
He was killed after being captured by security forces who besieged his compound in the northern city of Maiduguri using helicopters, artillery, foot soldiers, and armed police. An estimated 100 militants from Boko Haram also were killed in the fighting.
Nigeria's President Umaru Yar'Adua said security agents were ordered to attack the sect's fortified compound when the group started gathering fighters together in preparation for jihad.
Journalists report seeing Yusuf at a military barracks in Maiduguri after his capture. They say he had no visible injuries at the time and was able to stand up.
Nigerian government officials later claimed Yusuf was shot dead while trying to escape after he had been transferred to police headquarters.
Police commissioner Gregory Anyating said the authorities were continuing to hunt Boko Haram followers who armed themselves with knives, hunting rifles, and gasoline bombs and went on a rampage -- attacking churches, police stations, prisons, and government buildings in several northern states of Nigeria.
In recent months, police have been raiding Boko Haram hideouts and finding explosives and weapons. The sect's compound in Maiduguri included a laboratory that the military said was used to make bombs.
Boko Haram means "Western education is sinful" in the Hausa language that is spoken across northern Nigeria. The name reflects one of the main pillars of the sect's ideology. The group considers anybody who does not follow their strict ideology -- whether Muslim or Christian -- as an infidel.
The sect is sometimes called the "Nigerian Taliban" because it is loosely modeled after Afghanistan's Taliban -- using militant tactics to try to impose its own interpretation of Shari'a law across the country.
Most of Nigeria's Muslim leaders and believers dismiss Boko Haram's militant ideology as a perversion of Islam's peaceful teachings.
No conclusive evidence has been made public that links Boko Haram to Al-Qaeda or the Taliban in Afghanistan.
But Nnamdi K. Obasi, an analyst with the International Crisis Group, says a few Boko Haram followers had fought with Taliban forces in Afghanistan.
Yusuf himself was born in 1970. He had four wives and 12 children. He also had considerable private wealth and received a Western-style education.
His followers -- who come from diverse ethnic backgrounds in Nigeria's predominantly Muslim north -- say Yusuf also was educated in Iran.
Authorities say they fear Yusuf's death could provoke more violence in Nigeria in the future. Yusuf's followers in Boko Haram appear to be in disarray for now, but several hundred managed to escape -- some of them with weapons.
Nigerian Army officials say Yusuf's deputy, Bukar Shekau, also was killed in the clashes.
compiled from news agency material