Sen. James Lankford, R-Oklahoma, said Sunday that lawmakers want the whole story on the mission in Niger that killed four American soldiers.

"At this point we have conflicting stories. We want to be able to get the full, accurate story and get it right," Lankford said Sunday on CBS News' "Face the Nation."

While the Pentagon is looking into the details surrounding the ambush, members of Congress, including Lankford, have called for more transparency on the events surrounding the attack. Lankford said the key aspect is finding out what actually happened.

His comments came after Sen. John McCain, the Senate Armed Services Committee chairman, called on the Trump administration to be more forthcoming about the details of the ambush.

"We are coequal branches of government we should be informed at all times," McCain said on Friday.





According to Secretary of Defense James Mattis, the soldiers killed were not expecting enemy contact at the time they were ambushed earlier this month by a group of about 50 fighters affiliated with the Islamic State of Iraq and Syria (ISIS).

Lankford called the region in which the ambush took place "extremely unstable."

"A lot of weapons that came out of Libya are going down into this region," he said. "They're being used by Al Qaeda and ISIS-affiliated groups. We've had well over 100 U.N. troops that have been killed in Mali. It's one of the deadliest places for U.N. peacekeepers in all of the world. And so there are a lot of issues with this region."

Lankford said it's "extremely important" for U.S. forces to "stay engaged."

"We're advising and assisting all over the world to be able to help put down Al Qaeda, and ISIS, and other radical Islamic groups that are around the world that are seeking to terrorize not only the local communities, but as we've learned from Afghanistan it's not just an isolated region of the world that will never come after us. Obviously they have come after us before from these isolated regions," Lankford said.

The details of the Niger ambush have been slow to emerge, including the military's immediate response, CBS News' David Martin has reported.

The troops were on patrol about 120 miles north of Niger's capital. The risk of enemy contact had been evaluated as very low, so they did not have the kind of air cover that would be ready for a direct-action mission, in which the troops would have been prepared for direct combat. French aircraft were the first to respond, about 30 minutes after the ambush was reported.

Pentagon officials say an American reconnaissance aircraft was in the air but not watching over the patrol. It was only called in after the ambush started.

A U.S. law enforcement official confirmed to CBS News that the FBI is now assisting the military in its investigation into the ambush.