Unidentified militants killed at least 10 soldiers and wounded others in an attack on a military unit in northern Burkina Faso, the army said.
Burkina Faso has been overrun by Islamist violence this year with armed forces unable to contain it. Hundreds of civilians died and more than 150 000 fled as the influence of jihadist groups with links to al Qaeda and Islamic State spreads across the Sahel.
Monday’s attack occurred in the early hours of the morning in Koutougou in Soum province, an army statement said, without providing detail.
“In reaction to this barbaric attack, a vast air and land search operation is seeking to neutralise the many assailants,” the statement said.
Once a pocket of calm in the Sahel, Burkina suffered a spill-over of Islamist violence from neighbouring countries, including ethnic attacks similar to those destabilising Mali.
Deteriorating security prompted the Ougadougou government to declare a state of emergency in several northern provinces bordering Mali in December, including Soum.