Ouagadougou — Burkina Faso says an Islamist militant attack on an aid convoy has left 11 troops dead and dozens of civilians missing.

The Burkina Faso government said Tuesday that armed fighters ambushed a 150-vehicle military-escorted convoy carrying supplies to the northern town of Djibo.

It said at least 11 soldiers were killed and more than 50 civilians are missing.

The government said that the incident occurred Monday in the commune of Gaskinde in the northern province of Soum, where, since 2015, armed organizations affiliated with al-Qaida and Islamic State have taken over large swathes of territory.

Government spokesman Lionel Bilgo described the incident as "cowardly and savage."

The death toll could reach 60, according to French news agency AFP, which cited a security source who said "practically the entire caravan was burned."

The attack will likely exacerbate shortages of basic supplies, such as food and fuel in Djibo, which has been under a de facto siege for months by militant groups.

It may also increase concern about Burkina Faso, where some two million people are displaced amid increasing conflict and climate change.