It then took the French another hour to get fighter jets over the American troops, according to a new timeline provided by Gen. Joseph F. Dunford Jr., chairman of the Joint Chiefs of Staff. The disclosure doubles the amount of time the U.S. troops were believed to have fought without significant additional help.
"This is a very complex situation that they found themselves in, and a pretty tough firefight," Dunford said.
Four U.S. soldiers were killed and two others were wounded in the battle Oct. 4. Five Nigerien troops also died. The mission has ignited a political firestorm, raising questions about the U.S. military's broader mission in Africa and why one of the fallen soldiers, Sgt. La David Johnson, was not recovered for two days.
Senior U.S. officials are fairly certain, Dunford said, that when the soldiers left their base Oct. 3, their mission was to conduct a routine reconnaissance patrol to Tongo Tongo, a village near Niger's border with Mali. Less clear is whether they deviated from that task, whether they had adequate communications to call for help and how Johnson wound up missing. An ongoing investigation aims to answer those questions, Dunford said.
"What tactical instructions a commander on the ground gave at a given time to cause the units to maneuver, and where they may have been when Sergeant Johnson's body was found, those are all questions that will be identified during the investigation," he said, acknowledging the growing perception — both among the American public and lawmakers on Capitol Hill — that the Pentagon has not been forthcoming about the incident.
Several members of Congress have called for a hearing on the Niger operation, even after Defense Secretary Jim Mattis went to the Hill last week to discuss its details with Sen. John McCain (R-Ariz.), chairman of the Senate Armed Services Committee.
Dunford said that about 50 militants affiliated with the Islamic State launched the ambush in the middle of the morning as the U.S.-Nigerien patrol, comprising 12 Americans and 30 Nigeriens, headed away from the village en route to their base. The militants were armed with machine guns, small arms and rockets, he added.
U.S. officials are examining whether the militants were tipped off by someone in the village.
There are no indications U.S. troops requested help for the first hour, Dunford said. Once they did, a U.S. drone arrived overhead "within minutes," he added, and it captured video of the fight below.
It took another 30 minutes to launch the French Mirage fighters that came to soldiers' defense, and an additional 30 minutes for them to arrive on scene, Dunford said. So the soldiers were on their own for about two hours.
The Pentagon had said previously that jets were overhead within 30 minutes of the request. Dunford attributed the discrepancy to internal confusion as U.S. military officials assess what happened.
The situation's severity became more clear in Washington the night of Oct. 4, after Marine Corps Gen. Thomas Waldhauser, who oversees U.S. Africa Command, called Dunford to inform him that Johnson was still missing and to ask for additional help, Dunford said.
The Pentagon responded by deploying "national assets" from the United States to assist in the operation, Dunford said. He declined to provide specifics, but he was probably referring to a team of personnel assigned to the elite Joint Special Operations Command.
Dunford's remarks came as a dispute between the White House and Johnson's family continued to boil over Monday.
Myeshia Johnson, the fallen soldier's widow, said in an interview with ABC's "Good Morning America" that she was "very angry" about the way she was treated by President Trump in a condolence phone call placed last week. She said the president struggled to remember her husband's name.
Trump fired back on Twitter, saying he had a "very respectful" conversation with the widow and "spoke his name from beginning, without hesitation!"
Dunford declined to address the controversy but struck a markedly different tone. The Pentagon, he said, owes the families of the four slain soldiers — in addition to Johnson, Staff Sgt. Bryan Black, Staff Sgt. Jeremiah Johnson and Staff Sgt. Dustin Wright also were killed — "as much information as we find out about what happened."
Dunford also addressed the frustration expressed by Myeshia Johnson on Monday when she told "Good Morning America" that she was not allowed to view her husband's remains and questioned whether he was in fact inside the casket.
U.S. military policy calls for a casualty assistance officer to recommend at times for remains not to be viewed, but it also says that it is ultimately the family's decision.
"I can tell you what the policy is," he said. "I don't know what happened in the case of Mrs. Johnson, but we will certainly find out."
Despite the alarm over what transpired in Niger, the United States is unlikely to significantly shift its mission there, one of several countries where the Pentagon has long trained African forces to counter terrorism. There were about 800 U.S. troops in Niger at the time of the incident, and U.S. operations there already have resumed, Dunford said.
Overall, there are about 6,000 U.S. troops across the African continent, Dunford said. More than half are concentrated in Djibouti, with others in Tunisia, Senegal and Somalia.
Dunford promised that the Pentagon will release more information when it can.
"We owe the American people an explanation of what their men and women were doing at this particular time," Dunford added. "And when I say that, I mean men and women in harm's way anywhere in the world — they should know what the mission is and what we're trying to accomplish when we're there."