The head of a branch of the Islamic State Organization in West Africa claimed responsibility for an attack that killed four US special forces and four soldiers from Niger in October, the Nouakchott news agency said on Saturday.

The soldiers were killed when dozens of militants armed with automatic weapons and rocket launchers attacked their joint patrol near the village of Tungu Tongo on the border between Mali and Niger on October 4.

The attack drew attention to a US military presence in Niger where the United States is deploying 800 of its troops. The administration of President Donald Trump faces difficulties in justifying the deployment of US troops in the region.

Security officials said the attackers were Islamist militants loyal to Adnan Abu al-Walid al-Sahrawi, leader of the Islamic State Organization branch in the Sahara, but the report was not confirmed by the group operating along Mali’s coast with Niger and Burkina Faso.

“We declare our responsibility for the attack on the US commando last October in the Tongo Tongo area of ‚Äč‚ÄčNiger,” the independent news agency Nouakchott quoted the Sahrawi, who is seldom quoted as saying, as saying.

The Mauritanian agency sometimes takes precedence over obtaining information about the movements of Islamist fighters in the Sahara region. It was the first to announce the merger of major jihadi groups in Mali last year and exclusive reports were published in 2013 about a militant attack on a gas station in Algeria that killed 38 hostages.

Sahrawi said in his statement that he was also responsible for a car bomb attack on French troops on Thursday near the city of Minaka in Mali. He added that the attack resulted in the “killing of a number of French soldiers,” but the French army said in a statement that only three soldiers were wounded in the attack.

Jihadi groups are exploiting the chaos in the Sahara region to react vigorously and launch increasingly violent attacks on local and western targets there and in the semi-arid Sahel region to the south. These groups are the biggest threat to the stability of the region.