Capturing Boko Haram

A man, whom the Chadian military say they have taken prisoner for belonging to insurgent group Boko Haram, is seen in Gambaru February 26, 2015. The Chadian military nicknamed the man "the Butcher". REUTERS/Emmanuel Braun

Chadian soldiers walk in front of a building that Boko Haram insurgents used as their base before being driven out by the Chadian military in Dikwa, Nigeria, March 2, 2015. REUTERS/Madjiasra Nako

Debris is scattered in front of a building that Boko Haram insurgents used as their base before being driven out by the Chadian military in Dikwa, Nigeria, March 2, 2015. REUTERS/Madjiasra Nako

Chadian soldiers drive past the body of what they said was a Boko Haram fighter they killed in battle in Dikwa, Nigeria, March 2, 2015. REUTERS/Madjiasra Nako

A Chadian soldier walks past an armored vehicle that the Chadian military said belonged to insurgent group Boko Haram that they destroyed in battle in Gambaru, Nigeria, February 26, 2015. The Chadian military said that Boko Haram had taken the...more

A boy, who the Chadian military say is the son of a Boko Haram fighter the Chadian military killed during battle, stands next to soldiers in Gambaru, February 26, 2015. REUTERS/Emmanuel Braun

The logo of insurgent group Boko Haram is seen on the cracked windshield of an armored vehicle which Chadian military say they destroyed in battle in Gambaru, February 26, 2015. REUTERS/Emmanuel Braun

Chadian soldiers drive to the front line in the war against insurgent group Boko Haram in Gambaru, Nigeria, February 26, 2015. REUTERS/Emmanuel Braun

Chadian soldiers push a military pickup truck to get it out of the sand near the front line in the war against insurgent group Boko Haram in Gambaru, Nigeria, February 26, 2015. REUTERS/Emmanuel Braun

A prisoner suspected of being a member of insurgent group Boko Haram sits in the field base of Chadian soldiers in Gambaru, Nigeria, February 26, 2015. REUTERS/Emmanuel Braun

A man suspected of being a member of insurgent group Boko Haram sits tied up in the field base of Chadian soldiers in Gambaru, February 26, 2015. REUTERS/Emmanuel Braun

Weapons belonging to insurgent group Boko Haram that Chadian military say they took during battle are seen in Gambaru, February 26, 2015. REUTERS/Emmanuel Braun

Chadian soldiers drive near the front line during battle against insurgent group Boko Haram in Gambaru, February 26, 2015. REUTERS/Emmanuel Braun

A Chadian soldier fixes his headscarf while driving at the front line during battle against insurgent group Boko Haram in Gambaru, February 26, 2015. REUTERS/Emmanuel Braun

A Chadian military general inspects an armored vehicle, which the Chadian military say was taken by them from insurgent group Boko Haram during battle in Gambaru, February 26, 2015. REUTERS/Emmanuel Braun

A Chadian soldier peers into a burnt armoured vehicle, which the Chadian military say belonged to insurgent group Boko Haram, after the Chadians destroyed it during battle in Gambaru, February 26, 2015. REUTERS/Emmanuel Braun

A Chadian soldier rides atop a pickup truck next to a bag of rocket-propelled grenades in Gambaru, Nigeria, February 26, 2015. REUTERS/Emmanuel Braun

A Chadian soldier wears charms for protection near the front line during battle against insurgent group Boko Haram in Gambaru, February 26, 2015. REUTERS/Emmanuel Braun

Chadian soldiers drive through the town of Gambaru, Nigeria, February 26, 2015. REUTERS/Emmanuel Braun

Chadian soldiers cook food near the front line during battle against insurgent group Boko Haram in Gambaru, February 26, 2015. REUTERS/Emmanuel Braun

Chadian soldiers stand next to what they say was a camp for insurgent group Boko Haram, which the Chadian military said they destroyed in battle, in Gambaru, Nigeria, February 26, 2015. REUTERS/Emmanuel Braun

Chadian soldiers drive to the front line during battle against insurgent group Boko Haram in Gambaru, Nigeria, February 26, 2015. REUTERS/Emmanuel Braun

Chadian soldiers drive past the body of a man they say was a Boko Haram fighter the Chadian military killed in battle in Gambaru, Nigeria, February 26, 2015. REUTERS/Emmanuel Braun

The body of a man, believed to be a Boko Haram fighter and who was killed by the Chadian military during battle, lies in a field in Gambaru, February 26, 2015. REUTERS/Emmanuel Braun

Chadian soldiers drive near the front line in the war against insurgent group Boko Haram in Gambaru, Nigeria, February 26, 2015. REUTERS/Emmanuel Braun