DAKAR (Reuters) - French forces in northern Mali have killed around a dozen Islamist militants in the region of the Adrar des Ifoghas mountains, France’s defense ministry said on Monday.

No French soldiers were killed in the attack which took place on Saturday night, the statement said.

Malian military sources said the French operation was conducted between Boureissa and Abeissa, some 120 km (75 miles) from the northern desert town of Kidal, a stronghold of Tuareg separatist rebels.

The Islamist group was spotted by aerial surveillance, and engaged by French ground forces, one Malian source said.

France has deployed some 3,000 troops in its Barkhane mission to combat Islamist groups operating in the Sahara desert and the arid Sahel region that runs to the south.

Nearly two years after a French-led operation liberated the north of Mali from al Qaeda-linked rebels, the region remains prey to sporadic violence by Islamist militant and separatist groups, despite the deployment of a 10,000-strong U.N. peacekeeping mission.