An investigation has been launched into events on board a Royal Navy nuclear submarine.
The Daily Mirror reported that the Ministry of Defence was probing an "inappropriate relationship" between crew members and that the captain of the vessel, who has not been named, had been relieved of his duties pending the outcome.
The MoD refused to confirm the nature of the inquiry but said in a statement: "We can confirm the Royal Navy is undertaking an investigation. While this is ongoing, it would be inappropriate to discuss further."
There are strict Royal Navy rules about relationships on board vessels.
In 2014, the first female commander of a frontline warship in the history of the Royal Navy left her vessel amid claims she had an affair with a shipmate.
Commander Sarah West, who denied the relationship, was "removed from command" of the Type 23 frigate HMS Portland and re-appointed to another post.