September 7, according to related media reports, the U.S. Central Intelligence Agency's secret documents have once again been released.

Unlike in the past, the leaks were not of hacking tools used in attacks or software for surveillance missions, but of a missile control system.

The leaked documents are said to be four documents on the Armor Guard missile control system, as well as 37 related documents on the design and manufacture of the system. The leaked documents show that the missile launch system installed on the aircraft, developed by the U.S. Raytheon Company, can be used to command the airborne missile launch mission, the implementation of air-to-air and air-to-ground strike mission.

But the source said it was unclear why the CIA's engineering development team would have kept documents related to the missile control system, calling it "unusual".

Since March of this year, the CIA's so-called secrets have been made public on an almost weekly basis. The site has so far published 23 batches of documents in the "Vault 7" series. "Vault 7 is a large database dedicated to the collection and disclosure of CIA hacking and "modus operandi and tools of the trade."

The CIA has not yet responded to the story, according to US media reports.