There is one of these bases just down off Baja, down off the south of Los Angeles in California, off a place called Guadalupe Island – or Isla Guadalupe.
"The USS Nimitz was placed there to monitor them, and they have monitored over 100 of these UFOs coming and going, coming down from out of space and going under the water at that spot.
Being monitored under the water by the nuclear submarines that were attached to the USS Nimitz battle group. They have analysed this, and we know there is a base down there."
https://www.dailystar.co.uk/news/us-news/government-been-retrieving-alien-spacecraft-34099754?int_source=nba
US Government has been retrieving alien spacecraft since World War 2, claims source - Daily Star
A source claims that US involvement with UFO retrieval goes back as far was World War 2, and that it involved the CIA and other parts of the US Defense sector as well
https://www.dailystar.co.uk/news/us-news/government-been-retrieving-alien-spacecraft-34099754?int_source=nba