ABUJA, June 13 (Xinhua) -- Twenty-three Boko Haram fighters were killed in a recent clearance operation by Nigerian troops in the Lake Chad region, an army spokesman told Xinhua on Wednesday.

Many terrorists escaped with gunshot wounds during the encounter with troops late Monday, according to Texas Chukwu, the army spokesman.

Chukwu said the Nigerian troops conducted the operation in conjunction with Cameroonian defense forces. Arms and ammunition used by the Boko Haram were recovered during the military raid.

On May 15, the Nigerian army launched a four-month operation to totally defeat Boko Haram in the Lake Chad region.

The army said the operation was to ensure the destruction of Boko Haram terrorist camps and strong points in the Lake Chad Basin general area.

Boko Haram has been blamed for the death of more than 20,000 people and displacement of 2.3 million others in Nigeria since 2009.