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article_snippet: The leader of the Islamist extremist group Boko Haram Abubakar Shekau.
article_snippet: It has not been possible to verify exact numbers of those killed.
article_snippet: Nigeria's national security spokesman Mike Omeri is working to verify the reports while the military could not immediately be reached for comment.
article_snippet: Security operatives search  for information at the main gate to the Monday Market where the blast occurred in Maiduguri, Nigeria, earlier this month .
article_snippet: The Islamist uprising has claimed more than 13,000 lives since 2009 and President Goodluck Jonathan has faced fierce criticism over failure to contain the violence.