The two helicopters reportedly clashed at low altitude as they prepared to attack a group of jihadists, followed by French commandos, said Tuesday the French staff.
All the people on board, including six officers and six non-commissioned officers, were killed in the accident which occurred around 18:40 (18:40 GMT). The troops were part of Operation Barkhane, a 4,500-strong French force that supports the local army in the Sahel region against Islamist extremists.
This heavy toll, the largest in operation since 1983, caused a great deal of excitement in the army and political staff. A national tribute will be organized Monday to the Invalides.
“These thirteen heroes had only one goal: to protect us,” French President Emmanuel Macron said on Twitter.
French troops have been stationed in Mali since 2013, when they helped restore government control over the north of the country.
The region had fallen into the hands of militants associated with al-Qaeda following a local uprising and military coup the year before. Malian President Ibrahim Aboubacar Keita also paid tribute to the dead soldiers.
“They died for Mali, for the Sahel, for freedom and for the people,” Keita said in a statement.
The French also operate from bases in Niger and Chad against militant Islamist groups currently active in the Sahel region.
Monday’s operation took place in the Liptako region, in the “three border region” where Mali, Burkina Faso and Niger meet. The French army said its commandos had been operating on the ground for several days.
A few hours before the incident, they found the trail of a group of jihadists, who were in a van and motorcycle.
Helicopters and fighter jets were called to support the mission. A Cougar helicopter, carrying six mountain commandos and a mission commander, joined the force to coordinate the action and prepare to “pull” a person off the ground, said the staff.
However, he crashed on a Tiger helicopter “while maneuvering to prepare the enemy’s engagement,” and the two helicopters crashed to the ground a short distance apart, killing all people on board.
On Tuesday, many Operation Barkhane forces were in place for rescue and security operations in the area, the army said.
The incident comes weeks after 53 Malian soldiers and one civilian were killed in an alleged jihadist attack on a military post in the north.
According to the newspaper Le Figaro, a total of 23 French soldiers died in Mali on 10 November.