Up to six drones flew around the vessels at once in often low-visibility conditions close to Southern California's Channel Islands in a few days. The drones flashed lights, prompting a precautionary security response onboard the warships, according to Navy ship logs obtained by The Drive via a Freedom of Information Act request.

Information on the prolonged incident was also obtained via access to publicly available ship tracking data. Dave Beaty — a documentary filmmaker — made the initial discovery of crucial details about the drone flights around the USS Kidd, a Navy destroyer, according to the report.

This incident could effectively be a serious security breach.

The drone flights happened near San Clemente Island — home to strategic military facilities including one Navy SEAL training site, the Navy's only live firing range for ship-to-shore targets, and an airfield.

Inquiries into the baffling drone flights were immediately launched from intelligence officers and investigators in both the Navy and the FBI — and a special agent associated with the Naval Criminal Investigative Service, the director of the Maritime Intelligence Operations Center of the Navy's 3rd Fleet, and the FBI field office in Los Angeles. The Drive received emails emphasizing the high-level attention this incident received, with concerned parties extending all the way up to the chief of naval operations.

US Navy ships saw 'white light' hovering above

Some military authorities thought the Navy may have launched drones without informing the crew of the destroyers, but it was not made clear from the emails cited in the report whether this is what happened.

The drones themselves stayed in the air for at least 90 minutes, surpassing the capacities of commercially available drones, and flew at least 100 nautical miles, according to one case cited in the report, explaining the locations of ships in view of the aircraft.

The ship's logs suggested the drones could fly at the same speed as U.S. destroyers — moving at 16 knots in low-visibility conditions, which is also considered 1 nautical mile of visibility. The ship deployed an onboard intelligence unit — called a "SNOOPIE" team for Ship Nautical Or Otherwise Photographic Interpretation and Exploration team — to fully document the robotic aircraft.

Once the two drones were in view, the USS Kidd engaged security measures, restricting communications in a mode the ship's log calls "River City 1," reports The Drive's analysis. Two additional Arleigh Burke-class destroyers later reported hearing drones, with the USS Rafael Peralta spotting a "white light identified hovering over" the flight deck, read the ship's log.

'Drones' also seen by local cruise ship

Incredibly, the next night — July 15 — drones appeared once more later in the evening. The USS Russell documented heavy drone activity, including the mystery vehicles' dropping altitude and moving forward, backward, right, and left.

There was also a cruise ship nearby called the Carnival Imagination, which radioed the Rafael Peralta to reassure didn't come from them. The crew of the cruise ship informed the Navy ship that they'd seen up to five or six drones in their vicinity, according to the Peralta's ship log.

The extent of this perplexing development is still developing today, since the Navy has yet to make official comment on the matter, but the report suggests even more drones were spotted flying near warships on July 25 and July 30 — when military officers were still trying to compile and analyze information about the July 14 and July 15 incidents. The origin of these unidentified "drones" remains unknown, but it could signify advanced military aircraft tests from another advanced nation — although this is pure speculation.