As many as 12 civilians died in a raid against al-Qaeda in Yemen in late January, the head of the US military's Central Command has said.
"We have made a determination based on our best information available that we did cause ... between four and 12 casualties," US Army General Joseph Votel told a Senate hearing on Thursday, adding he accepted responsibility for shortcomings in the operation.
Critics have questioned the value of the raid against al-Qaeda in the Arabian Peninsula, authorised by President Donald Trump, in which US Navy SEAL William "Ryan" Owens also died.
The Pentagon said it is carrying out an investigation into the details surrounding Owens' death and another review into the destruction of a US military helicopter in the operation.
Votel said a separate "exhaustive after-action review" had not found incompetence, poor decision-making or bad judgment.
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"As a result, I made the determination that there was no need for an additional investigation into this particular operation," Votel said.
