North Korean defectors, now living in South Korea, prepare to release balloons carrying propaganda leaflets denouncing North Korea's late leader Kim Jong-Il at Imjingak, near the Demilitarized zone (DMZ) separating South and North Korea on December 28, 2011 in Paju, South Korea. (Photo by Chung Sung-Jun/Getty Images)

Medic James E. Callahan of Pittsfield, Mass., gives mouth-to-mouth resuscitation to a dying soldier in war zone D, about 50 miles northeast of Saigon, June 17, 1967. Thirty-one men of the 1st Infantry Division were reported killed in the guerrilla ambush, with more than 100 wounded. (Photo by Henri Huet/AP Photo)

A South Korean military vehicle drives past barricades at the military check point, near the Demilitarized zone (DMZ) separating South and North Korea on December 20, 2011 in Paju, South Korea. (Photo by Chung Sung-Jun/Getty Images)

A Chinese couple take pictures in an interactive installation art work named “You and Me” on Valentine's Day at 798 Art Zone on February 14, 2012 in Beijing, China. (Photo by Feng Li/Getty Images)

Marines of the Baltic Fleet forces of the Russian Navy train in the zone of obstacles during military exercises at the Khmelevka firing ground in the Kaliningrad region, Russia on November 24, 2021. (Photo by Vitaly Nevar/Reuters)

Police officers try to stop medical students as they protest against Sri Lanka's crippling economic crisis, outside the Health Ministry in Colombo on April 6, 2022. (Photo by Ishara S. Kodikara/AFP Photo)

A participant stands next to a robot during the St. Petersburg International Economic Forum (SPIEF) in Saint Petersburg, Russia on June 15, 2022. (Photo by Maxim Shemetov/Reuters)

A 5.5 metre massive crocodile makes mince meat out of a bull shark in Kakadu's Adelaide River on August 5, 2014 in Kakadu, Australia. The crocodile forced the bull shark into the mangroves and devoured the bull shark. A 43 year old Sydney father took these exclusive photos in the Northern Territory. (Photo by Andrew Paice/Getty Images)