South Korean police officers show their martial arts' skills during the official launch ceremony of the 2012 Seoul Nuclear Security Summit on February 15, 2012 in Seoul, South Korea. The Korean National Police Agency launched a security squad, exclusively established for the successful hosting of the 2012 Seoul Nuclear Security Summit. The 2012 Seoul Nuclear Security Summit will be held in Seoul from March 26-27, 2012. (Photo by Chung Sung-Jun/Getty Images)

Somali women sing as they celebrate the election of President Mohamed Abdullahi Mohamed in the streets of Somalia's capital Mogadishu, February 9, 2017. This election is important because it may establish a pattern of peaceful change of government as well as continue to grow Somalia’s institutions especially for a country that has not heard a stable government for more than two decades. (Photo by Feisal Omar/Reuters)

The first autonomous and electric shuttle of PostAuto Schweiz in the old village of Sion, Switzerland, June 2016. (Photo by Ruben Sprich/Reuters)

Burning effigies of winter during a celebration of Maslenitsa festival (Pancake Week) at the Etnomir (Ethnoworld) cultural and educational center in Kaluga Region, Russia on March 1, 2020. The holiday celebrates the end of winter and marks the arrival of spring. (Photo by Sergei Bobylev/TASS)

A participant in costume and make-up poses for a photo during a Halloween parade at Walibi park in Wavre, Belgium, October 31, 2018. (Photo by Yves Herman/Reuters)

A combination of pictures shows people taking photos of themselves in Tiananmen Square as they celebrate National Day marking the 67th anniversary of the founding of the People's Republic of China, in Beijing October 1, 2016. (Photo by Damir Sagolj/Reuters)

Lightning strikes near Jacobsdorf at the Oder-Spree district in eastern Germany, September 1, 2015. (Photo by Patrick Pleul/AFP Photo)

Pro-Russian separatists from the Chechen “Death” battalion take part in a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. Chanting “Allahu Akbar” (God is greatest), dozens of armed men in camouflage uniforms from Russia's republic of Chechnya train in snow in a camp in the rebel-held east Ukraine. They say their “Death” unit fighting Ukrainian forces has 300 people, mostly former state security troops in the mainly-Muslim region where Moscow waged two wars against Islamic insurgents and which is now run by a Kremlin-backed strongman. (Photo by Maxim Shemetov/Reuters)