IS-linked group claim attacks on French, US troops in Africa
The group, led by Adnan Abu Walid Sahraoui, said it was behind "an attack against an American commando unit in Niger in October".
On October 4, four US and four Niger troops were killed in an ambush at Tongo Tongo, a village close to the Mali border.
That attack had been blamed on the jihadists but it is only now that the group claimed responsibility.
The Islamists also claimed responsibility for an attack in Mali's restive northeast on Thursday in which three French troops were injured, one seriously, in a suicide bomb attack, said the ANI news agency, which tracks jihadist groups operating in the Sahel region south of the Sahara.
Islamic extremists linked to al-Qaeda took control of the desert north of Mali in early 2012, but were largely driven out in the French-led military operation launched in January 2013, but large tracts of the country remain lawless.
According to an AFP count, 18 French soldiers have been killed in Mali since the launch of Operation Serval, which has since been replaced by Operation Barkhane, a broader offensive deployed in five countries - Mali, Mauritania, Niger, Chad and Burkina Faso.
These countries form the so-called G5 Sahel, a French-supported group that last year launched a joint military force to combat jihadism.
Last month, Saudi Arabia pledged 100 million euros towards the five-nation force, while the United Arab Emirates offered 30 million euros.
The date of the attack in Mali coincided with the fifth anniversary of the start of the French operation there.
The Islamists group in its statement also claimed responsibility for attacks last year in Burkina Faso.