The Malian army, however, said it had repulsed attacks on bases in the Timbuktu region.

Jama'at Nusrat al-Islam wal Muslimeen (JNIM) took control of the Niafounke camp Friday with the help of a suicide-bomb vehicle, the group said on its Al-Zallaqa Foundation media platform.

The statement was verified Saturday by SITE, a US organisation that follows radicalised groups.

Tens of soldiers were killed or wounded in the battle, and two captured, JNIM claimed.

It released photos showing five armoured vehicles it claimed to have captured, along with weapons and ammunition.

JNIM often abandons camps they capture after a few hours.

The group also claimed to have hit another army camp, a few miles away in Goundam, with mortar fire.

The Mali military said on social media that the attacks had been "energetically repelled."

"After artillery fire on the two camps, the assailants tried in vain to occupy them and were routed," it said.

Verifying claims by either side is complicated because access to the region is difficult and dangerous.

Since 2012, Mali has been ravaged by groups affiliated to Al-Qaeda and Islamic State, as well as by self-declared self-defence forces and bandits.

The north in particular has seen intensified military clashes following the recent withdrawal of UN forces at the demand of the ruling junta, which set off fighting between the military and Islamist and separatist forces to control the area.