The US Army has punished six people for their roles in a 2017 mission in Niger that resulted in the ambush deaths of four Americans and five allied Nigerien troops, The New York Times reported on Saturday.

The ambush occurred on October 4, 2017 as a unit of 12 American special forces soldiers and 30 Nigerien troops, returning from a village near the Malian border, were overrun by scores of jihadists.

An investigative report released by the Pentagon in May said that while US soldiers had fought bravely and four "died with honour," they had not been properly prepared for the mission. Investigators cited "individual, organisational and institutional failures."

Those being disciplined, the Times said on Saturday, include Captain Mike Perozeni, the leader of the Green Beret team, as well as his second in command, a master sergeant whose name has been withheld.

The paper said a letter of reprimand to Perozeni cited the insufficient training and a lack of mission rehearsals.

Two senior officers who approved the mission and oversaw the ill-fated operation were not reprimanded, according to the newspaper.

The Pentagon did not immediately respond to an AFP request for confirmation of the report's details.

It has been tight-lipped about the nature of the mission in Niger - the existence of which surprised many Americans.

The Times account said Perozeni's Green Beret unit, Team 3212, had headed toward the Niger-Mali border in pursuit of an Islamic State group leader named Doundoun Cheffou.

After intelligence located him, an operation was planned against the leader's camp by a helicopter-borne team of American commandos and Nigerien troops, along with Team 3212.

But bad weather led to the helicopter mission being canceled. Team 3212 proceeded to the now-empty campsite. It was ambushed by some 50 heavily armed Islamic State fighters while returning to its outpost.

The ambush claimed the largest loss of American lives in combat in Africa since the "Black Hawk Down" incident in Somalia in 1993.

It also touched off debate about the presence of the 800 American troops in Niger and the larger purpose of the US military in Africa.

General Thomas Waldhauser, head of Africa Command, said in May that US forces had since become "far more prudent" in their missions and had beefed up their firepower.

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