U.S. intelligence officials believe that the Middle East was the final destination of North Korean-made weapons aboard a Georgian-flagged plane that was detained by Thai authorities last week.

Dennis Blair, the U.S. Director of National Intelligence, said in an opinion piece published in the Washington Post on Friday that teamwork among U.S. agencies and partners abroad led to the interdiction of a Middle East-bound cargo of North Korean weapons last week.

This is the U.S. administration’s first official comment on the destination of the North Korean weapons.

Blair said that improved collaboration among 16 U.S. intelligence agencies also contributed to the detection and confiscation of the weapons.