The soldiers said the bodies were found in Damasak in Mobbar Local Government Area of Borno State in north-eastern Nigeria, a town they entered on Saturday.
Nigeria’s troops had renewed their onslaught against the Boko Haram terrorist after the nation’ general elections were shifted by six weeks to March 28 and April 11.
In an interview with the BBC, Nigeria’s President, Goodluck Jonathan, predicted that all territories would be taken back from the Boko Haram within a month.
“They are getting weaker and weaker by the day,” he said.
The victims, many with their throats slits and some decapitated, may have been killed some time ago, reports suggest.
Chadian army Colonel, Azem Bermandoa Agouna, said he had visited the grave and seen “about 100 bodies spread under a bridge just outside the town”.
Together with the Nigerian Army, forces from Chad, Niger and Cameroon are involved in an offensive against the Islamic militants who are controlling parts of north-eastern Nigeria.
In the renewed offensive, two out of three states, where the Boko Haram terrorists have been trying to establish an Islamic State, have been reclaimed from the Boko Haram terrorists.
Nigeria is preparing to hold presidential elections on 28 March and the Armed Forces, including the Multi Natonal Joint Task Force (MJTF) have reclaimed many towns that have been captured by the terrorist group.