An attack on a military camp near the town of Inates in western Niger has left 16 soldiers dead.
Following the raid on Monday afternoon near the Mali border, the gunmen escaped with a dozen military vehicles.
It's the same region where an ambush by IS' West African branch killed 28 soldiers in May.
The attack comes just days ahead of the African Union summit in Niger's capital Niamey.
Security has deteriorated in recent months, with France and the US deploying thousands of troops to counter IS and al Qaeda terror threats.
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