No group claimed immediate responsibility for the bomb, but jihadist violence in Burkina Faso has been blamed on militants linked to both Al-Qaeda and Islamic State groups.

"A homemade explosive was used in an attack Friday morning against a military unit," on patrol in a wildlife reserve in Soum province, leaving five dead, a security source told AFP.

"Reinforcements were sent to the zone to clear the area while the wounded were evacuated."

A wave of attacks at December killed 35 civilians, mostly women, and dozens of soldiers in an assault on a military base and a town in the north of the country.

Burkina Faso, as well as neighbouring Mali and Niger, has seen frequent jihadist attacks which have left hundreds of people dead since the start of 2015 when Islamist extremist violence began to spread across the Sahel region.

According to the UN, around 4,000 people were killed in jihadist attacks in the three Sahel countries last year.

There are 4,500 French troops deployed in the Sahel region as well as a 13,000-strong UN peacekeeping force in Mali to fight insurgents, backing up national forces of the G5 -- Chad, Burkina Faso, Mali, Mauritania and Niger.