Nigeria claims Boko Haram chief may be dead

The leader of Boko Haram, an armed separatist group behind a deadly uprising aimed at creating an Islamic state in northern Nigeria, may have been killed in a shoot-out with security forces, the Nigerian Army said Monday. 

Lt. Col. Sagir Musa said in a statement that intelligence reports suggest Abubakar Shekau, who Musa described as "the most dreaded and wanted Boko Haram terrorists leader" may have died last month.

The Nigerian military said Shekau was mortally wounded in an attack on a forest hideout on June 30. He was then taken over the border into Cameroon, where he was believed to have died between July 25 and Aug. 3, according to authorities.

But the military failed to provide any video or photographic evidence to back their claims. Meanwhile a man purported to be Shekau himself earlier addressed claims that he had been killed in a video message obtained by news agency AFP on August 12. 

"You have not killed Shekau," the person in the video said while seated with a Kalashnikov resting on his right shoulder -- a pose Shekau often adopted in such videos. "We are in good health."

The Nigerian military has countered that the video is not authentic.

Though the death of Shekau would be a blow to Boko Haram's campaign it is unlikely to mark the end of the organization, which has several factions. Spin-off groups have claimed responsibility for kidnapping and killing Westerners and are believed to operate independently.

Authorities had earlier claimed that Shekau was killed in a 2009 assault, but he appeared less than a year later in video clips circulated in Nigeria. 

The U.S. State Department named Shekau a “Specially Designated Global Terrorist” in June 2012. The United States, concerned that West Africa could become a springboard for attacks by armed groups, had put a $7 million bounty on Skekau, who has repeatedly denounced the West and criticized the United States for its treatment of Muslims. 

In May, after Nigerian president Goodluck Jonathan declared a state of emergency, the country’s security forces launched a major offensive against Boko Haram. The Nigerian military deployed thousands of troops in the northern part of the country and launched aerial attacks on the group’s suspected hideouts.

Boko Haram, founded in 2002, wants to impose Islamic law in Nigeria's north, and, alongside other spin-off armed groups, has become one the biggest threat to stability in Nigeria.

Shekau, who has been blamed for a campaign of deadly attacks across Africa’s largest oil-producing country, assumed the leadership of Boko Haram when its founder Mohammed Yusuf was killed in police custody during a crackdown in 2009. 

Since Shekau took command, the group's insurgency has intensified, killing thousands in the last two years. He has sworn to bring down the government of President Jonathan.

Many of the attacks have targeted places of worship, often churches, but Muslims have also been killed in the country, which is made up of 50 percent Muslims and 40 percent Christians, according to the CIA’s World Factbook. 

Since 2010, more than 1,500 people have been killed in the unrest, according to The Associated Press.

Al Jazeera and wire services