Back in July 2019, a swarm of technologically advanced drones buzzed around a fleet of U.S. Navy destroyers—and, despite multiple high-level inquiries into the incident, officials still have no idea who was flying them. The encounters were first reported by The Drive website last month, which said the mystery drones managed to match the warships’ high speed, operated in low-visibility conditions at night, and flew for over 90 minutes—way longer than what commercially available drones can sustain. Adm. Michael Gilday, chief of naval operations, was asked Monday if the Navy had identified the drones that flew near the ships off Southern California. He responded: “No, we have not.” Asked if the aircraft were “extraterrestrial,” Gilday said he had “no indications at all of that.” According to NBC News, the flights sparked concerns of a serious security breach and prompted immediate inquiries from investigators in the Navy and the FBI, but it seems that their investigations hit a dead end.