More than 100 bodies have been found in a mass grave in northeast Nigeria after a town was reclaimed from Boko Haram terrorists . The bodies - many with their throats slit and heads cut off - were found underneath a bridge in the town of Damasak , after it was retaken earlier this month by troops from Chad and Niger . It is believed the victims may have been killed more than two months ago , due to the fact the bodies were severely decomposed . Scroll down for video . Brutal : Abubakar Shekau , leader of the Islamist extremist group Boko Haram , preaching his messages of hate . The insurgents have lost ground to army forces in recent weeks . Victory : Chadian soldiers celebrate after reclaiming the town of Damasak . They were later horrified to find a mass grave outside of the town where more than 100 bodies had been dumped . Colonel Azem Bermandoa Agouna said several of the victims had been decapitated , while others had been shot . He said : 'There are about 100 bodies spread around under the bridge just outside the town . 'There are heads here and bodies there , the mass grave has become like a termite mound . ' He claimed the massacre probably occurred about two months ago and added : 'This is the work of Boko Haram . ' The Islamist uprising , which initially began as a campaign against Western education , has claimed more than 13,000 lives since 2009 . In a recent chilling development , the sinister group recently allied themselves with the Islamic State terrorists in Syria and Iraq . Pledge : A Boko Haram flag flutters from an abandoned command post in the town of Gamboru . The terror group recently pledged allegiance to the Islamic State . Chad and Niger launched an intensive ground and air offensive against Boko Haram in the area earlier this month , quickly reclaiming Damasak from the terrorists . According to army source , the militants suffered heavy losses in the push , with an estimated 200 killed in fighting last Sunday . Boko Haram had held the town since last November , when they killed around 50 people and forced another 3,000 to flee , according to the UN 's High Commissioner for Refugees . The Nigerian military has been struggling for years to stamp out the movement and President Goodluck Jonathan , who is facing an election next weekend , has faced fierce criticism over his government 's failure to contain the violence . Fighting back : A photo released by the Nigerian Army shows soldiers after reclaiming the town of Goniri . The presidential and parliamentary polls were initially due in February but were postponed by the election commission which cited security fears . Nigeria has claimed major recent gains against the Islamists with the help of coalition partners Cameroon , Chad and Niger , achieving in just over one month what for years it had failed to do on its own . Two out of three of the worst-hit northeast states -- Yobe and Adamawa -- have been declared 'cleared ' while the third , Borno , is expected to be liberated 'soon ' , the military said this week . Major towns such as Bama and Dikwa are among some 36 localities recaptured , with just three said to be still in rebel hands . Sorry we are not currently accepting comments on this article .
The gruesome discovery was made after town of Damasak was reclaimed . Soldiers find decomposed bodies with throats slit and heads cut off . A man who lives in the area says he saw a group of soldiers carrying away one body, while another soldier carried another.