The Pentagon has concluded its reviews of a 2017 ambush that left four U.S. soldiers dead in the African nation of Niger and said it found the discipline it meted out to be adequate.

Acting Secretary of Defense Patrick Shanahan has accepted that conclusion, which was the result of a monthlong review conducted by four-star Army Gen. Robert Brown that did not go beyond the scope of the initial investigation conducted by Special Operations Africa Command. Brown found the actions taken, primarily against junior officers, were adequate.

Based on an examination of the review, "I am satisfied that all findings, awards, and accountability actions were thorough and appropriate," Shanahan said in a statement issued Wednesday.

A 12-member Army special forces unit was accompanying 30 Nigerien forces on a mission to capture or kill a high-level Islamic State group leader in West Africa when they were outnumbered and attacked by more than 100 extremists carrying small arms just outside the village of Tongo Tongo.

The release of the 176-page unclassified report Wednesday ends more than a year of reviews after the Pentagon wrapped up an internal investigation into the Oct. 4, 2017, ambush. The report detailed a series of "individual, organizational, and institutional failures and deficiencies that contributed to the tragic events" but "no single failure or deficiency" to blame for what happened.

The investigation resulted in the implementation of 20 recommendations on issues including training, turnover, equipment and improved procedures, according to the Pentagon.

The report said U.S. forces didn't have time to train together before they deployed and didn't do preparatory battle drills with their Nigerien partners. The mission was hastily planned with lack of attention to detail because of time-sensitive intelligence, received hours earlier, that could lead to capture of a high-value target.

Investigators found that Special Operations Command in Africa had no process to deal with time-sensitive or real-time mission approvals and the command seemed implicitly to allow for last-minute notice of operations.

Nine individuals have been disciplined, mainly with letters of reprimand or administrative action. Maj. Gen. Marcus Hicks, who was serving as the commander of special operations forces in Africa at the time of the attack, was the most senior officer punished.

That has left some lawmakers and family members of the fallen soldiers asking whether junior officers were unfairly being forced to take the brunt of the blame.

Among them is Rep. Ruben Gallego, D-Ariz., who issued a statement Thursday critical of the military's handling of the review.

"From the beginning, the investigation into what happened that day has been poorly handled at all levels. One thing is clear: mistakes were made that cost these men's lives," said Gallego, a member of the House Armed Services Committee. "Their families — and the American public — deserve clear answers about what happened, who will be held accountable, and what will be done to prevent this from ever happening again."

Rep. Frederica Wilson, D-Fla., noted in a statement Thursday that one senior official involved was even in line for a promotion, and she was scathing in her assessment.

Shanahan's "failure to hold senior commanders accountable (is) quite frankly baffling, and yet another example of what happens when someone with questionable qualifications for the job he holds is tasked with such a complex problem," Wilson said, noting that he has no military experience.

Wilson's constituent, Army Sgt. La David T. Johnson, was one of the soldiers killed in the ambush. Wilson noted that he had been sent on a mission without proper intel or equipment and was "woefully unprepared to participate in counterterrorism operations."

She said the families are still pleading for answers and the Pentagon's "failure to provide them has opened new wounds that a medal of valor or redacted copy of an insufficient investigative report cannot heal."

The Pentagon said the Army has approved nine awards for valor, including four awarded posthumously to the soldiers killed in the ambush and ensuing firefight.

Killed in the attack were Johnson, 25, of Miami Gardens, Florida; Staff Sgt. Bryan C. Black, 35, of Puyallup, Washington; Staff Sgt. Jeremiah W. Johnson, 39, of Springboro, Ohio; and Staff Sgt. Dustin M. Wright, 29, of Lyons, Georgia.

Four Nigerien troops were also killed, and two American soldiers and eight Nigerien forces were wounded.

Wright and La David Johnson were awarded the Silver Star; Black and Jeremiah Johnson were awarded the Bronze Star with V for valor. Jeremiah Johnson was also posthumously promoted to Sgt. 1st Class.

The U.S. military in Africa has taken steps to increase the security of troops on the ground, adding armed drones and armored vehicles and taking a harder look when American forces go out with local troops. As result of the firefight, a team on patrol in Africa now would not be in an "uncovered position," according to the Defense Department.

The Pentagon said in November that it plans to reduce its counterterrorism forces in Africa over the next several years.

The move is in line with the Trump administration's belief that the main challenge to U.S. security and prosperity is strategic competition with China and Russia rather than threats from extremist groups like the Islamic State group.

___

Follow Tami Abdollah on Twitter at https://twitter.com/latams