A suicide bomber killed four people and injured six in an attack on a checkpoint at the entrance of the town of Tessalit in Mali on Wednesday.
Two of the dead are UN peacekeeping troops from Chad.
The bomber blew up his explosives-filled vehicle at the checkpoint, according to Olivier Salgado, spokesman for the UN peacekeeping mission in Mali.
French planes evacuated the wounded, according to a spokesman for Serval, France's military force in Mali.
This spring, French troops pushed Islamic militants out of north Mali after they seized control of the region following a March 2012 coup.
More from GlobalPost: In Mali, Al Qaeda now controls an area the size of France
But some experts are warning that many Islamic fighters may simply have retreated and waited for new opportunities to attack as France recalls its soldiers.
Currently, there are 3,000 French troops in Mali, but France plans to reduce that number to 1,000 men by the end of January 2014.
Top UN envoy Albert Koenders said earlier this month that various attacks by Islamic militants in Mali in recent weeks are a "wake up call'' to security forces that the job of restoring security is far from complete.