U.S. Military Investigating Suspected ISIS Video of Dead American Soldiers in Niger Ambush

Members of the 3rd Special Forces Group, 2nd battalion cry at the tomb of US Army Sgt. La David Johnson at his burial service in the Memorial Gardens East cemetery on October 21, 2017 in Hollywood, Florida. Sgt. Johnson and three other US soldiers were killed in an ambush in Niger on October 4. Gaston De Cardenas/AFP/Getty

The Pentagon is investigating a series of Twitter posts that appear to show images and footage of the Islamic State militant group (ISIS) raid in Niger that killed four American soldiers.

U.S. Africa Command, known as AFRICOM, is probing the social media posts by a user named "Mohammed Mahmoud Abu Maali" who alleges to have obtained footage from ISIS's Sahel affiliate, known as the Islamic State in the Greater Sahara, or ISGS, of the attack.

Twelves U.S. soldiers and 30 Nigerian forces came under fire on October 4 from jihadis armed with machine guns and rocket-propelled grenades near a village called Tongo Tongo, in an assault that U.S. officials believe was a set-up.

"USAFRICOM is aware of a post on Twitter purporting to show a U.S. soldier from the Oct. 4 ambush in Tongo Tongo, Niger," AFRICOM said in a release seen by The Army Times.

One of the now-deleted tweets purported to show the bodies of U.S. soldiers wearing combat uniform and with U.S. military patches. It claims, in French, to have received a ten-minute video from the ISIS affiliate.

The images remain unverified but were enough for the U.S. military to open an investigation. The video was not released on official ISIS channels, including its self-proclaimed news agency Amaq.

"We are reviewing the post and determining the veracity of the tweet and the assertions that there is an associated video," the release continued.

"We cannot comment further on this issue, or the ongoing investigation related to the Oct. 4 ambush until the investigation is complete."

The Twitter user in question wrote: "The video shows one side of the attack, the American dead, some photos were shot by an American soldier, but ISIS took them after the photographer was killed."

If confirmed, it is not the only video to be released from the scene of the attack. Footage released to ABC News by retired Lieutenant Colonel Rudolph Atallah showed armed men on motorcyles in the area close to the site of the attack.

"It says if we capture them what are we going to do with them. One of them says we'll decapitate them, another guy says we'll fight them with weapons," Atallah said, suggesting prior plans of an attack against enemy combatants.

Staff Sgt. Bryan Black, Staff Sgt. Dustin Wright, Staff Sgt. Jeremiah Johnson and Sgt. La David Johnson were all killed in the ambush near the village that officials believed to be sympathetic to ISIS.

The Trump administration came under fire after the ambush for appearing to be hesitant to deliver details about how the operation went so awry as to claim the lives of four U.S. soldiers. Almou Hassane, the mayor of Tongo Tongo, said after the attack that "the attackers, the bandits, the terrorists have never lacked accomplices among local populations."

The ISGS is a relatively new and local branch of ISIS that has conducted several small attacks in the region, particularly in Burkina Faso, which neighbors Niger. The jihadi affiliate gave its allegiance to ISIS and the group accepted its bayah, or pledge, in October 2016.

The ISIS affiliate in the area that stretches across six African countries from Senegal to Chad is overshadowed by more dominant radical Islamist groups, in this case Al-Qaeda's affiliates—Al-Qaeda in the Islamic Maghreb, Ansar Dine and Al-Mourabitoun.