U.S. Army/Spc. Zayid Ballesteros

Just two months after four U.S. service members were killed by ISIS militants during a deadly ambush in Niger, their fellow Green Berets struck back against the terror group.

Department of Defense officials announced on Wednesday that Army Special Forces personnel and Nigerien security forces killed 11 ISIS fighters during an intense firefight in December. According to the New York Times, which first reported the news, no U.S. or Nigerian military personnel were injured during the incident.

The combined U.S.-Nigerian force "came under fire from a formation of violent extremists" believed to be affiliated with ISIS-West Africa during a mission in the Lake Chad Basin region, U.S. Africa Command spokesman Pat Barnes told Task & Purpose. And although previous reports had indicated that the ill-fated Oct. 4 ambush that cost four members of the 3rd Special Forces Group their lives had deviated from its original mission, AFRICOM characterized the Dec. 6 encounter as conventional.

"The purpose of this mission was to set the conditions for future partner-led operations against violent extremist organizations in the region," Barnes told Task & Purpose. "There was no aspect of this mission focused on pursuing enemy militants, and the combined force was postured to respond as necessary in case contact with the enemy occurred."

The firefight signals an uptick in aggressive U.S.-led counterterrorism operations in Niger and neighboring countries in the months after the Oct. 4 ambush. Just weeks after the tragic incident, the Army announced it was "boosting" its security, intelligence, and training operations in the Lake Chad Basin region that's become a hotbed for Islamic militants returning home from the battlefields of Iraq and Syria.

But the firefight also remains the first instance of prolonged combat between U.S.-led and ISIS forces in Niger formally acknowledged by AFRICOM since the Oct. 4 ambush apart from, as the New York Times notes, apart from a single line in a report delivered to Congress by the Trump administration regarding the use of U.S. military force abroad. And with Secretary of Defense James Mattis currently reviewing the findings of the DoD's internal investigation into the causes of the Oct. 4 ambush, it's unclear how news of the incident might reverberate in the Pentagon and on Capitol Hill.

As the fight against ISIS in Iraq and Syria winds down, it's almost certain U.S. military personnel will increasingly encounter ISIS fighters dug in across the African continent. And according to AFRICOM officials, soldiers are ready for it.

"Our forces do operate in unstable areas and are occasionally exposed to danger from enemy forces," Barnes told Task & Purpose. "When such a situation occurs, our personnel are authorized to respond to threats and violence appropriately."

Senior Pentagon correspondent Jeff Schogol contributed reporting

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