Chadian troops rescue 85 Nigerian hostages from Boko Haram

From Aminu Abubakar, for CNN

Updated 1535 GMT (2335 HKT) August 17, 2014

A video of Abubakar Shekau, who claims to be the leader of the Nigerian Islamist extremist group Boko Haram, is shown in September 2013. Boko Haram is an <a href="http://www.cnn.com/2014/02/27/world/africa/nigeria-year-of-attacks">Islamist militant group waging a campaign of violence</a> in northern Nigeria. The group's ambitions range from the stricter enforcement of Sharia law to the total destruction of the Nigerian state and its government. Click through to see recent bloody incidents in this strife-torn West African nation:
Photos: Boko Haram: Nigeria's crisis
A video of Abubakar Shekau, who claims to be the leader of the Nigerian Islamist extremist group Boko Haram, is shown in September 2013. Boko Haram is an Islamist militant group waging a campaign of violence in northern Nigeria. The group's ambitions range from the stricter enforcement of Sharia law to the total destruction of the Nigerian state and its government. Click through to see recent bloody incidents in this strife-torn West African nation:
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Photos: Boko Haram: Nigeria's crisis
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Bodies lie in the streets in Maiduguri, Nigeria, after religious clashes on July 31, 2009. Boko Haram exploded onto the national scene in 2009 when <a href="http://www.cnn.com/2012/01/02/world/africa/boko-haram-nigeria/index.html">700 people were killed </a>in widespread clashes across the north between the group and the Nigerian military.
Photos: Boko Haram: Nigeria's crisis
Bodies lie in the streets in Maiduguri, Nigeria, after religious clashes on July 31, 2009. Boko Haram exploded onto the national scene in 2009 when 700 people were killed in widespread clashes across the north between the group and the Nigerian military.
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An official displays burned equipment inside a prison in Bauchi, Nigeria, on September 9, 2010, after the prison was attacked by suspected members of Boko Haram two days earlier. About <a href="http://www.cnn.com/2010/WORLD/africa/09/08/nigeria.prison.break/index.html">720 inmates escaped</a> during the prison break, and police suspect the prison was attacked because it was holding 80 members of the sect.
Photos: Boko Haram: Nigeria's crisis
An official displays burned equipment inside a prison in Bauchi, Nigeria, on September 9, 2010, after the prison was attacked by suspected members of Boko Haram two days earlier. About 720 inmates escaped during the prison break, and police suspect the prison was attacked because it was holding 80 members of the sect.
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Nigerian President Goodluck Jonathan, second from left, stands on the back of a vehicle after being <a href="http://www.cnn.com/2011/WORLD/africa/05/29/nigeria.president.inauguration/index.html">sworn-in as President </a>during a ceremony in the capital of Abuja on May 29, 2011. In December 2011, Jonathan declared a <a href="http://www.cnn.com/2011/12/31/world/africa/nigeria-state-of-emergency/">state of emergency</a> in parts of the country afflicted by violence from Boko Haram.
Photos: Boko Haram: Nigeria's crisis
Nigerian President Goodluck Jonathan, second from left, stands on the back of a vehicle after being sworn-in as President during a ceremony in the capital of Abuja on May 29, 2011. In December 2011, Jonathan declared a state of emergency in parts of the country afflicted by violence from Boko Haram.
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