Transcript for New details on ambush of U.S. service members in Niger

We want to move on to new information we're learning about the ambush in Niger that killed four American special ops soldiers. Ian Pannell is on the ground in Niger with the latest on this attack and the hunt for those responsible. Ian, good morning. Reporter: Dan, Paula, a new piece to the puzzle regarding the attack that left four American soldiers dead. A senior intelligence official telling ABC news there was a convoy of three trucks fleeing the deadly ambush, two making it out to the so-called kill zone but the third truck was cut off from the other vehicles unable to communicate with the group. Staff sergeants black, Johnson and Wright were in this vehicle, sergeant la David Johnson in the third reportedly opening fire on the attackers but it's unclear when. The official telling ABC the stranded vehicle was hit with mortar and gunfire killing all three soldiers. Two hours later French jets came no the battle zone flying low which caused the attackers to scatter preventing more fatalities. The remaining survivors then evacuating by helicopter. But many questions remain back home. Move all, what was their mission and should they have been better supported? And why was sergeant la David Johnson left behind, his body only recovered two days later? It's a dangerous business so I didn't know specifically. I gave them authority to do what's right so that we win. Reporter: So what we're now hearing from officials this morning there is a military operation being planned against the perpetrators of this attack and other attacks in the area. We're being told this has been accelerated because of the death of the four American soldiers, we don't know exactly when this is taking place but we're told it's soon and will have American support.

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