A United States Coast Guard icebreaker is on its way to help free two ships stuck in the Antarctic.
A research ship, the Akademik Shokalskiy, became trapped in ice after a blizzard on Christmas Eve. A Chinese vessel, the Snow Dragon, then became stuck trying to help.
Twenty-two crew are still on board the Akademik Shokalskiy after a helicopter rescue mission airlifted the ship's 52 scientists and tourists to safety last week.
Lisa Martin from the Australian Maritime Safety Authority, which has been co-ordinating the rescue efforts, says the Polar Star is on of the largest ships in the US Coast Guard Fleet.