Documents released recently under FOIA detail how several US Navy destroyers were harassed repeatedly for weeks by swarms of mysterious drones. The incidents occurred during the summer of 2019, when at least three ships recorded clusters of unidentified aerial vehicles in their vicinity. Attempts to shoot down the drones failed due to the small size of the targets. The US Navy has launched an investigation into the unexplained incidents, but at this time no photos or explanations have been made public.