(CNN/Meredith) -- With enemy forces rapidly closing in on his position, Army Sgt. La David Johnson decided he had to move, evading gunfire alone and on foot for over half a mile before eventually taking cover under a thorny tree. It was here that the 25-year-old South Florida native would make his final stand.
What happened to Johnson, and how he became separated from the rest of the Green Beret-led team after it was ambushed by more than 100 ISIS fighters in Niger last October, was one of the key mysteries surrounding the attack, which left four US soldiers and four Nigeriens dead.
The Americans killed were Johnson, Staff Sgt. Bryan C. Black, Staff Sgt. Jeremiah W. Johnson and Staff Sgt. Dustin M. Wright.
But new details about Johnson's fate -- including an explanation for why his body was recovered in a remote area of the northwestern African country by Nigerien troops nearly 48 hours after he was discovered missing -- emerged Thursday when the Pentagon released a summary of a months-long military investigation into the incident.
According to a summary of the report, the 12-member team and their partner Nigerien troops were ambushed "by a large enemy force" immediately after their convoy stopped near the village of Tongo Tongo to resupply.
One of the Nigerien vehicles appeared to depart the area immediately, and the team radioed their headquarters saying they were under attack, but they did not request support.
The team leader assessed that his combined force could defeat the threat but soon realized that the enemy force was much larger than anticipated, and he ordered his troops to withdraw to the south, the report summary said.
The convoy eventually departed, but it was at this critical moment that one of the vehicles carrying three of the US soldiers killed in the ambush became separated from the group.
Realizing that they were missing members of their team and after repeated attempts to reach them via radio, two soldiers from the rest of the US force attempted to return to the ambush site on foot to find their teammates. They soon encountered the enemy and entered into a gun battle.
It was during this firefight that Johnson returned fire from one of the US vehicles, expending all the ammunition in his M240 machine gun. He switched to a M2010 sniper rifle and continued fighting, according to the summary.
After receiving increasing enemy fire from ISIS fighters equipped with trucks mounted with machine guns, the team leader ordered his remaining force of Americans and Nigeriens to withdraw.
It was at this point that Sgt. La David Johnson became separated. While his surviving teammates believed Johnson received the order to withdraw, he, along with two Nigerien soldiers, was unable to get into his vehicle because of enemy fire and was unknowingly left behind.
Johnson and the Nigerien soldiers escaped on foot. The two Nigerien soldiers were killed and Johnson ran some 950 meters -- evading enemy gunfire -- and eventually took cover behind a single tree and returned fire.
Johnson was eventually pinned down by an ISIS truck armed with a machine gun and he was killed by small arms fire.
Because Johnson had evaded on foot "to a location outside the immediate search area of responding forces" his body was not recovered until 48 hours after it was realized he was missing even though the investigation states that the search began immediately and did not stop until he was found, the Pentagon's summary said.
A village elder eventually found Johnson's body and alerted Nigerien forces, which eventually returned the body to US custody. The summary said that Johnson's hands were never bound and he was never captured alive or executed.
"The search never stopped," Army Maj. Gen. Roger L. Cloutier told reporters, adding that "it took a long time to find him" because Johnson ran a long way from where he was last seen.
"Efforts to locate SGT L. Johnson were initially delayed by errant reporting that SGT L. Johnson was being held in a village north of Tongo Tongo near the Mali border," the report said.
The summary also said "Johnson's hands were not bound and he was not executed but was killed in action while actively engaging the enemy."
"[He] made his last stand where he fought until the end under a dense thorny tree," Cloutier said.
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