Two Tongo Tongo villagers said they saw the bodies of the other United States of America soldiers killed in the attack, Staff Sgts.

The villagers in Africa who found the body of a South Florida soldier said he was apparently shot in the back of the head, and his wrists were bound behind his back, according to a report published on The Washington Post.

"This mission allowed the investigation team to gather information and determine the facts related to the ambush that killed four US soldiers and four Niger Force Soldiers", it added. "His two arms were tied behind his back", he said.

"The back of his head was a mess as if they had hit him with something hard, like a hammer", recalled Alassane, who said he also saw the body. Alassane said Johnson was only wearing socks; his shoes were missing.

Three weeks ago, the widow of one of the slain US military personnel in Niger had at his burial, said she was unsure her husband's remains were indeed in the coffin. Special Forces - or Green Berets - killed in an ambush believed to have been orchestrated by militants linked to the Islamic State group in Niger.

The Tongo Tongo village chief claims the soldier's remains were discovered face down almost a mile from the scene of the fire fight.

US investigators on Sunday returned to a village in Niger where four American soldiers were killed in an ambush in October carried out by Islamist militants, the military said. Last month, after a briefing on the Niger attack, McCain said the Pentagon was making progress on the investigation and that he was "pleased at the cooperation" members of Congress were getting from officials.

The Pentagon and Federal Bureau of Investigation are conducting a probe into the ambush to determine if any errors were made in intelligence prior to the mission.

Johnson was one of four US soldiers and five Niger servicemen killed in an October incident, but Johnson wasn't found for two days after he went missing.

The Post, citing an unnamed USA military official, reported that it appears that the soldiers' mission was changed after they left the base and were sent to assist another team in taking out a top ISIS target called Dadou.

Three other soldiers were killed in the October 4 ambush.