A demonstrator wears a mask during a protest inside the Bay Area Rapid Transit (BART) Civic Center station on August 15, 2011 in San Francisco, California. The hacker group “Anonymous” staged a demonstration at a BART station this evening after BART officials turned off cell phne service in its stations last week during a disruptive protest following a fatal shooting of a man by BART police. (Photo by Justin Sullivan/Getty Images)

A protester with his face smeared with soot from burning barricades stands in the Musaga neighbourhood of Bujumbura on May 6, 2015. Government and opposition rivals are meeting in Burundi in a bid to end deadly demonstrations against a third term bid by the president, as regional foreign ministers arrived to add pressure. (Photo by Phil Moore/AFP Photo)

Wadha al-Sayyed, wife of captive Lebanese soldier Khaled Moqbel, protests for his release and government action, near burning tyres blocking a road in Beirut, December 15, 2014. More than two dozen members of the Lebanese security forces are being held by Sunni Islamists. (Photo by Hasan Shaaban/Reuters)

A student activist is detained during a silent protest after Thailand's election commission filed charges against a group for posting “foul and strong” comments online criticising a military-backed draft constitution, in Bangkok, Thailand April 27, 2016. (Photo by Jorge Silva/Reuters)

Smokes rises from a fire as a Palestinian protester takes cover during clashes with Israeli troops near the Jewish settlement of Beit El, near the West Bank city of Ramallah October 9, 2015. (Photo by Mohamad Torokman/Reuters)

A riot policeman punches Greek photojournalist Tatiana Bolari during a demonstration in Athens' Syntagma (Constitution) square October 5, 2011. Police officers attacked several members of the press covering protests, injuring at least two members of the media. (Photo by Yannis Behrakis/Reuters)

A man reacts as he tries to extinguish a burning Christmas tree at Festival Walk mall in Kowloon Tong, Hong Kong, November 12, 2019. Anti-government protesters smashed windows and set fires in the mall on Tuesday, including to a big Christmas tree. (Photo by Thomas Peter/Reuters)

Female activists perform a choreography originated in Chile, and inspired by the Chilean feminist group Las Tesis, to protest against gender violence and patriarchy in front of the Greek parliament at Athens' Syntagma Square on December 22, 2019. (Photo by Louisa Gouliamaki/AFP Photo)