°®Âþµº

A member of the Air Force has been taken into custody in connection with an April attack in that wounded four fellow service members, the Air Force said on Tuesday.

The initially blamed the attack in Green Village in eastern Syria on indirect fire, possibly a rocket strike.

It later said further investigation showed the blasts were the result of "deliberate placement of explosive charges" at an ammunition holding area and shower facility, and officials said they were looking into the possibility of an insider attack.

A US airman has been taken into custody stateside in conjunction with the attack in Green Village, Syria, back in April

— Kyle Rempfer (@Kyle_Rempfer)

The Air Force declined to identify the service member.

"As part of an ongoing investigation, on June 16, an Airman was taken into custody stateside in conjunction with the attack in Green Village, Syria," Air Force spokeswoman Ann Stefanek said in a statement.

"After reviewing the information in the investigation, the Airman's commander made the decision to place him in pretrial confinement."

CNN was the first outlet to report the arrest.

U.S. military officials say around 900 US troops are operating in Syria, mainly training and advising partner forces fighting the remnants of Islamic State militants.