A visit by a U.S. aircraft carrier to South Korea prompted a warning from the sister of North Korea’s leader that Washington and Seoul “should not test” the communist regime.

The U.S. aircraft carrier USS Carl Vinson arrived at the southern port city of Busan in South Korea on Sunday as a show of force against North Korea, South Korea's navy said.

The powerful sister of North Korean leader Kim Jong Un has threatened a high-profile response to the arrival of a U.S. aircraft carrier in South Korea and other U.S. military activities