Russia’s main intelligence agency has released a video of three crew members of the Ukrainian vessels that were seized on Sunday.
The FSB put out the video, showing interviews with three seamen, all of whom confirmed that they violated the Russian border.
It was not immediately possible to ascertain if the men were talking under duress.
One of them was clearly reading from a teleprompter.
Russian border guards on Sunday fired at three Ukrainian navy vessels as they were trying to make their way through the Kerch Strait near Russian-occupied Crimea.
The Russians then seized the ships and their crews.
The escalation over the weekend was the first overt military confrontation between Russia and Ukraine.
- Press Association