May 10 (UPI) -- Pentagon investigators on Thursday blamed multiple "individual, organizational and institutional failures" for the ambush that left four U.S. solders dead in Niger in October 2017.
The six-month investigation, which resulted in an eight-page summary report released Thursday, determined no single person or entity was to blame for the deaths.
The Oct. 4 assault left four members of a team of Green Berets -- Staff Sgt. Bryan C. Black, Staff Sgt. Jeremiah W. Johnson, Sgt. La David Johnson and Staff Sgt. Dustin M. Wright -- dead along with at least five Nigerien soldiers. Another American soldier, Sgt. 1st Class Brent Bartels, was injured.
The report offered a brief look at the morning of the ambush, when the 11-man team undertook heavy fire near the town of Tongo Tongo, where they encountered swamps and wooded areas. The Pentagon said the four U.S. soldiers who died did so in combat and that none were captured alive by the enemy.
The report said the U.S. team had not undergone proper training nor had it rehearsed its mission ahead of time due to "personnel turnover." Additionally, the operation had not been approved at the proper level of command.
The Green Berets were on a routine mission to meet with village elders
"This investigation identifies individual, organizational and institutional failures and deficiencies that contributed to the tragic events of October 4, 2017," the report said. "Although the report details the compounding impact of tactical and operational decisions, no single failure or deficiency was the sole reason for the events."
Investigators credited Nigerien and French forces for responding to the scene and "likely saving the lives of the surviving members of the" U.S. team.
"The [French] Mirage jets were not able to drop ordnance due to the confusion on the ground, but low-level passes over the fight caused the [Islamic State] terrorists to break action and retreat," the Pentagon said. "French helicopters arrived later and evacuated the surviving U.S. soldiers."
Along with the report, investigators released an edited recreation of the battle based on 143 witnesses and one survivor of the attack who revisited the scene of the battlefield to assist the probe.
Gen. Roger Cloutier, who oversaw the investigation and gave a briefing on its findings Thursday afternoon, said that though there were a "tremendous amount" of interviews conducted, there were still elements of the attack left unknown.
"He has directed a number of specific actions to examine, evaluate and make recommendations of DoD personnel practices to improve units' readiness and lethality," she said.
An earlier version of this story incorrectly reported that senior defense official David Trachtenberg was injured in the Niger attack. He was not.