"There are 20 allegations pending credibility assessment," Meyer said. "This includes 13 credibility assessments in Iraq and seven in Syria."
A credibility assessment is a preliminary investigation undertaken by the US military to determine if there were civilian casualties and if the US forces caused them.
"It’s important to note that the current environment on the ground in Syria makes investigating allegations extremely challenging," he pointed out.
Meyer also said that until the ongoing investigations and associated processes are completed, "we cannot discuss details."
The Defense Department takes reports of non-combatant casualties seriously, and assesses all incidents as thoroughly as possible, he added.