North Korean soldiers keep watch at the bank of the Yalu River, near the North Korean town of Sinuiju, opposite Dandong in China's Liaoning province, September 10, 2016. (Photo by Thomas Peter/Reuters)

Uniformed participant dance during a mass rally and parade in the capital's main ceremonial square, a day after the ruling party wrapped up its first congress in 36 years by elevating him to party chairman, in Pyongyang, North Korea, May 10, 2016. (Photo by Damir Sagolj/Reuters)

North Korean children wave to people on a Chinese tourist boat on the banks of Yalu River near the Chongsong county of North Korea, opposite the Chinese border city of Dandong, May 8, 2011. (Photo by Jacky Chen/Reuters)

In a photo taken on September 11, 2019, North Korean students pose for photos in Chonji lake, or “Heaven lake”, as they visit the crater of Mount Paektu, near Samjiyon. Mount Paektu has long been considered the spiritual birthplace of the Korean nation and is a place of pilgrimage for tens of thousands of North Koreans every year, who are trained from birth to revere their leaders. (Photo by Ed Jones/AFP Photo)

Chunhun (R), the leader of Japan's North Korea fan club called sengun-joshi, or military-first girls, and other members practice a Moranbong Band dance in Tokyo, Japan on November 2, 2017. (Photo by Toru Hanai/Reuters)

A bench engraved with the name of the grounded Costa Concordia cruise ship (seen at rear) is seen washed up on the shore of Giglio island, in this January 20, 2012 file photo. The trial of Francesco Schettino, accused of causing the deaths of 32 people in the 2012 Costa Concordia cruise ship disaster, nears its climax with a verdict expected over the coming days. The prosecution has demanded that he be jailed for 26 years but the captain denies all the charges against him. Schettino was the commander of the vessel when it came too close to shore and hit rocks off the Tuscan holiday island of Giglio. (Photo by Paul Hanna/Reuters)

Traffic police stand at the side of a road in Pyongyang on November 25, 2016. (Photo by Ed Jones/AFP Photo)

Mr. Zhong Hua, of Johns Hopkins University School of Medicine, took this image of the peripheral nerves (those outside of the brain) in an 11.5-day-old mouse embryo, magnified five times. (Photo by Zhong Hua)