North Korean military participate in the celebration of the 70th anniversary of the founding of the ruling Workers' Party of Korea.

North Korea's military said on Friday it would "ruthlessly ravage" the United States if Washington chose to attack, as a U.S. aircraft carrier group headed for the region amid fears the North may conduct a sixth nuclear weapons test.

"Our toughest counteraction against the U.S. and its vassal forces will be taken in such a merciless manner as not to allow the aggressors to survive," North Korea's official KCNA news agency quoted its military as saying in a statement.

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