The U.S. captain of the Greenpeace ship seized by the Russian coast guard has described the stress and fear he and the other 29 people on board felt when they were thrown into Russian jails, with no idea when they would get out.

Most of them were released on bail last week after spending two months behind bars, and all were expected to be out soon.

Peter Willcox, a veteran Greenpeace activist who was the ship's captain, told The Associated Press on Sunday that "the hardest thing was the uncertainty, the anxiety, the damn fear. Everybody lost weight during the first three weeks, and not because of food, but because of stress."

All 30 still face charges of hooliganism for a protest against oil drilling in the Arctic.