The Central Intelligence Agency (CIA) must acknowledge whether an armed drone program exists, a federal appellate court ruled on Friday.

The American Civil Liberties Union (ACLU) took the CIA to court after filing a Freedom of Information request about drone strikes overseas. The CIA denied the request, saying it could not release any documents because even acknowledging the existence of the program would harm national security.

“The existence or nonexistence of CIA records responsive to this request is a currently and properly classified fact, the disclosure of which reasonably could be expected to cause damage to the national security,” the CIA argued to the court, which initially agreed.