A riot policeman watches as a police vehicle burns in Braamfontein, Johannesburg, South Africa, Tuesday, October 25, 2016. Rioters in South Africa set a police vehicle on fire Tuesday and stoned vehicles near a Johannesburg university that has been the scene of sometimes violent protests by students demanding free education. The violence broke out in streets near the University of the Witwatersrand at around the same time that student protesters met and marched off the campus, South African media reported. (Photo by Yeshiel Panchia/AP Photo)

Riot police clash with demonstrators protesting against proposed pension reforms outside the Congress in Buenos Aires on December 18, 2017. Protesters angry at proposed pension and welfare reforms attacked police close to Argentina's congress building in Buenos Aires on Monday, the second protest in a week to turn violent. Activists lobbed stones, bottles and firecrackers at police as huge crowds demonstrated against pension reforms proposed by the center-right government of President Mauricio Macri. (Photo by Eitan Abramovich/AFP Photo)

Migrants with a stick, stones and knife fight with each other after a brawl erupted over a place in an overcrowded train heading to the Serbian border at the train station in Gevgelija, The Former Yugoslav Republic of Macedonia, 14 August 2015. (Photo by Georgi Licovski/EPA/EFE)

Migrants with a stick, stones and knife fight with each other after a brawl erupted over a place in an overcrowded train heading to the Serbian border at the train station in Gevgelija, The Former Yugoslav Republic of Macedonia, 14 August 2015. The number of migrants passing through Macedonia increases day by day, local sources said. From the beginning of the year to mid-June 2015, nearly 160,000 migrants landed in the southern European countries, mainly Greece and Italy, on their way to wealthier countries in Western and Northern Europe, according to estimates by the International Organization for Migration (IOM). (Photo by Georgi Licovski/EPA)

A Palestinian protester uses a sling to hurl stones towards Israeli troops during clashes near the Jewish settlement of Bet El, near the occupied West Bank city of Ramallah October 5, 2015. Violence intensified in Jerusalem and the West Bank on Sunday after Israelis were targeted in two stabbing attacks and a Palestinian was killed in a clash with Israeli troops, officials said. (Photo by Mohamad Torokman/Reuters)

Afghan child stands in front of a makeshift shelter after an earthquake in Gayan village, in Paktika province, Afghanistan, Friday June 24, 2022. A powerful earthquake struck a rugged, mountainous region of eastern Afghanistan early Wednesday, flattening stone and mud-brick homes in the country's deadliest quake in two decades, the state-run news agency reported. (Photo by Ebrahim Nooroozi/AP Photo)

Facade of the “Porcelain House”, built by Chinese collector Zhang Lianzhi, on November 1, 2008 in the Heping district of Tianjin, China. Over 400 million porcelain fragments, 5,000 ancient vases, 4,000 antique china dishes and bowls, over 20 tons of crystalline rocks and agate, 400 white marble stone carvings were incorporated in the five year refurbishment of the unique French styled house. (Photo by China Photos/Getty Images)

A mob attacks a female police officer accused of shooting a protester in the Buterere neighborhood of Bujumbura, Burundi, May 12, 2015. Protesters opposed to the president's decision to run for a third term chased, beat and stoned the woman, who was later handed back to the police. (Photo by Goran Tomasevic/Reuters)