Pentagon aerial 0308
CNN  — 

The US military is set to launch a formal investigation into a drone strike in Syria in early May, six weeks after the operation and following reports it killed a civilian rather than a senior al-Qaeda leader as first claimed, three defense officials familiar with the matter told CNN.

The anticipated opening of the more formal inquiry, known as a 15-6, is the clearest sign yet that US Central Command may have botched the drone strike in northwest Syria on May 3.

In the immediate aftermath of the strike, Gen. Erik Kurilla, the commander of Central Command, and his staff had high confidence that they had targeted and killed a senior al-Qaeda leader. Despite knowing it would take several days to get a positive identification of the target since the US has no presence in that part of Syria, CENTCOM tweeted about the operation without naming the target. The tweet, which came at the direction of Kurilla, promised more information “as operational details become available.”