According to the publication, US submarines detected the unidentified objects using sonar. It is not specified where and when the objects were detected
However, it is claimed that their behaviour cannot be explained in terms of existing technology.
No other details of what happened are given.
This information comes after a video of an unidentified flying object that was spotted off the US coast in July 2019 by pilots of the USS Omaha of the US Navy was published online.