The video, which shows a group of young men on motorbikes brandishing rifles and machine guns, was provided to ABC News by Ret. Lt. Col. Rudolph Atallah, a former U.S. military expert on West Africa. He says it came from villagers in the vicinity of the attack.

According to Atallah, a former U.S. counterterrorism official and senior fellow at the Atlantic Council, the video was recorded by Abu Walid, the leader of a local militant group which has pledged allegiance to the Islamic State, or ISIS.

“I think he is the candidate for this,” Atallah told ABC News. “He is certainly one of the high value individuals that the U.S. government is looking at.”