The fighting took place in Ngouboua, a western village in Lake Chad, bordering Cameroon, Niger, and Nigeria, on Sunday.
This clash comes months after the start of a military operation in western Chad following another attack, allegedly by Boko Haram, on October 27, in which some 40 soldiers were killed.
Hundreds of small islands are located in the bordering Lake Chad region where groups such as Boko Haram and the Islamic State of West Africa Province (ISWAP) are active.
International organizations estimate that more than 35,000 people have died as a result of attacks by these Islamist groups, while some 2.7 million people have been forced to abandon their homes and farmland.
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