inson

As the USS Carl Vinson ploughed through seas off South Korea on Tuesday, rival North Korea warned the United States of "merciless" attacks if the carrier infringes on its sovereignty or dignity during U.S.-South Korean drills.

F-18 fighter jets took off from the flight deck of the nuclear-powered carrier in a dramatic display of U.S. firepower amid rising tension with the North, which has alarmed its neighbors with two nuclear tests and a series of missile launches since last year.