Four US and five Nigerien soldiers were killed and two Americans were wounded in the October 4 attack.
The officials said the unit was not under orders to conduct a kill or capture mission on the leader. Such missions are typically reserved for other elite special operations forces teams.
The 12-member team was conducting a routine patrol alongside 30 Nigerien soldiers when they were asked to check on a site where a high-value target was believed to have been previously, one official said.
The official emphasized that the terrorist leader was known to no longer be at the location, something the US military continues to believe, and the team was tasked only with collecting possible intelligence.
The mission’s perceived threat level was not changed because military leaders still believed the team would not encounter enemy fighters.
“At no time were they ever tasked to be part of a capture or kill operation” of a high value target, the official said.
The team did not encounter any enemy forces at the site and left the location.
On their way back to their operating base, they stopped in a separate village in order to enable the Nigerien troops to replenish supplies. While there, US troops met with local leaders as a courtesy.
The official said that it is “quite probable” that someone in the village tipped off the ISIS-affiliated terrorists that US forces were in the village, setting up the ambush.
The village elders themselves are not suspected.
CNN was told previously by multiple US officials that the survivors of the ambush said in initial after-action interviews that they felt the villagers were attempting to delay their departure and may have been complicit in the ambush.
The new details come a day after Joint Chiefs of Staff Chairman Joseph Dunford told reporters that the troops were on their way back to their operating base when they were ambushed by 50 ISIS fighters.
The ISIS affiliated attackers used mortars, rocket-propelled grenades, technical vehicles and heavy machine guns according to one defense official.
About one hour into the firefight, the team requested support.
“My judgment would be that that unit thought they could handle the situation without additional support,” Dunford said. “And so, what we’ll find out in the investigation [is] exactly why it took an hour for them to call.”
A remotely piloted drone aircraft arrived overhead within minutes of the request for help. It was tasked to provide surveillance and reconnaissance and to capture video of the scene, the general said.
But a US defense official told CNN that the US drones in Niger are not authorized to be armed, which meant the aircraft was unable to conduct airstrikes in support of the troops on the ground.
Armed French Mirage jets arrived about one hour later — two hours after the troops made initial contact with enemy forces.
The official said the jets were authorized to strike but did not.
CNN also learned Tuesday that the Green Beret-led team was on one of its first patrols in the country after arriving just weeks earlier, according to two US defense officials.
One of the officials said the team was on its first patrol when it was ambushed, while the second official said the team was either its first or second patrol.
Previously the military has said there had been 29 similar patrols without incident, but the officials have clarified those 29 patrols were conducted by the task force as a whole, not by this specific unit that came under attack.
The four soldiers killed in the ambush in Niger had relatively little combat experience, according to Army service records obtained by CNN. One of the four killed in action had never been deployed overseas while the other three had each undergone one deployment to Afghanistan, Nigeria and Jordan. None of the four soldiers received the Army’s combat infantry badge or combat action badge, which are given to soldiers participating in units that have been engaged in active ground combat. CNN had been previously told by defense officials that this particular team had only been in Niger for “weeks” and that this was one of their first patrols.
The team’s lack of experience on the ground may not have been a decisive factor in how the ambush took place, but it may have played a role in how the soldiers reacted once the firefight began, according to CNN military analyst retired Col. Steve Warren.
Their newness may have had an impact on how quickly the team called for support and the way evacuations were conducted, Warren said.
During Monday’s Pentagon briefing, Dunford told reporters that there is no indication that the US troops were operating outside their orders at the time of the ambush.
“I don’t have any indication right now to believe or to know that they did anything other than operate within the orders that they were given,” Dunford said. “That’s what the investigation’s all about. So I think anyone that speculates about what special operations forces did or didn’t do is doing exactly that, they’re speculating.”
Still, Dunford said the military will be investigating whether the planned reconnaissance mission changed.
“It was planned as a reconnaissance mission,” he said. “What happened after they began to execute, in other words, did the mission change? That is one of the questions that’s being asked. It’s a fair question, but I can’t tell you definitively the answer to that question. But, yes, we’ve seen the reports, we’ve seen the speculation.”
A defense official told CNN on Tuesday that the chief of staff to the commander of US Africa Command, Major Gen. Roger Cloutier Jr., is leading the formal investigation into the deadly ambush.
One US soldier, Sgt. La David Johnson, was separated from the 12-member team as it was ambushed by the ISIS fighters, and his body was recovered 48 hours later nearly a mile away from the central scene of the ambush, four administration officials familiar with the early assessment of what happened told CNN on Friday.
Dunford said Monday that he could not definitely confirm reports that Johnson was found nearly a mile away, but that those details would come to light as part of the investigation.
“I think we owe the families and American people transparency,” Dunford said.
Asked Tuesday why Johnson’s body was found so far away from the central scene of the ambush, one defense official told CNN that combat happens quickly and soldiers seek cover as best they can.
In the simplest terms, Johnson was separated from his unit in the chaos of battle, the official said.