Ten Chadian soldiers were killed in combat in the north of Mali near the border with Algeria, the African nation’s army reported on Sunday.

On Friday, another thirteen Chadian troops died in clashes with Islamist insurgents who were pushed out of the major cities and towns of northern Mali in a French military intervention last month. One French soldier died in fighting in the same area last week.

France launched airstrikes against insurgents in its former colony in early January when they appeared to advance on the capital city Bamako. It followed up with ground deployments numbering over 3,000 soldiers who were able to aid the Malian army in forcing the insurgents to abandon their strongholds and seek refuge in the northern deserts and mountain ranges of the sub-Saharan country.

The rebels’ defeats appeared to have split their ranks with the more mainstream Tuareg secessionist groups vying for peace while hardline Islamists, including the Tuareg Ansar Dine and members of Al Qaeda’s North African wing, press on in the inhospitable terrain of northern Mali. A political settlement of the north Mali conflict will probably require a greater measure of autonomy for the Tuaregs who live there.

A West African peacekeeping force, to be composed of up to 8,000 soldiers from neighboring countries, mainly Chad and Nigeria, is to take over from the French to prevent the Islamists from resurging. President François Hollande has said the conflict enters a “new phase” when his forces start withdrawing from Mali. But the West Africans still struggle to organize their military operation. They will likely need more support from France and other Western nations to provide airlifts, ammunition, communications equipment and field hospitals to be able to mount an effective force for a prolonged period of time.