John Bacon

USA TODAY

North Korea marked the birthday of leader Kim Jong Un's grandfather with a rousing concert in Pyongyang that featured a video simulation of a nuclear missile attack destroying what appears to be an unidentified U.S. city.

The video simulation, obtained by Western news sites Wednesday, shows at least one ballistic missile being fired and crossing the Pacific before multiple missiles appear to strike the U.S. The video then shows an American flag and a cemetery superimposed with flames.

The video was unveiled Sunday during a performance by North Korea's State Merited Chorus for participants of a military parade marking the 105th birthday of Kim Il Sung. He ruled North Korea from its establishment in 1948 until his death in 1994, when his son Kim Jong Il began a reign that lasted until his death in 2011.

The video comes at a time of high tensions between the U.S. and North Korea. The U.S. has expressed outrage at a series of missile and nuclear tests by Pyongyang, and North Korean leader Kim has been equally critical of a massive military exercise involving hundreds of thousands of South Korean and U.S. troops.

Vice President Mike Pence visited South Korea this week, pledging solidarity with Seoul and warning North Korea that "the era of strategic patience is over." Pence, visiting Japan on Wednesday, issued another warning.

"The United States of America will always seek peace but under President Trump, the shield stands guard and the sword stands ready," Pence said from the deck of the USS Ronald Reagan aircraft carrier in Tokyo Bay.

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Videos depicting such destruction are not new for Pyongyang. North Korea released a dramatic video in 2016 called "Last Chance" that showed a simulated nuclear strike on Washington, complete with animation of a missile slamming into the earth near the Lincoln Memorial. The four-minute video, backed by a musical score reminiscent of U.S. TV Westerns of the 1960s, includes a mushroom cloud and an American flag going up in flames.

In 2013, a simulated video showed nuclear launches against the United States reaching four sites, including Washington, D.C., California, Hawaii and what the announcer described as Colorado Springs, but appeared to be Arkansas.

The birthday of Kim Il Sung, April 15, is a national holiday in North Korea called the Day of the Sun. Festivities stretch for months, but the Sun Festival takes place over several days in April.