Mariam, a 9-year-old girl, carries her brother as she stands with other children at an underground ancient cemetery in Jabal al-Zawiya in the southern countryside of Idlib November 26, 2014. Residents are using ancient caves and cemeteries as underground shelters to hide in during shelling from forces loyal to President Bashar al-Assad. Picture taken November 26, 2014. (Photo by Khalil Ashawi/Reuters)

Rescue workers stand near dead bodies washed ashore in Ton Sai Bay in Thailand's Phi Phi island in this December 28, 2004 file photo. On December 26, 2004, a magnitude 9.15 quake off the coast of Indonesia's Aceh province triggered an Indian Ocean tsunami that killed around 226,000 people in Indonesia, Sri Lanka, India, Thailand and nine other countries. (Photo by Luis Enrique Ascui/Reuters)

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)

Monastic dormitories stand on the hillside at the Serthar Wuming Buddhist Study Institute on November 4, 2006 in Serthar County of Garze Tibetan Autonomous Prefecture, Sichuan Province, China. The Wuming Buddhist Study Institute is located in Larung Gar Monastery on an altitude of 3,700 meters (about 12,136 feet). The institute has the largest conglomeration of monks and nuns in Tibetan Areas, with over 40,000 monastics from the Tibet Buddhism Nyingma School, Gelug School, Sakya School and Kagyu School, including more than 10,000 nuns. (Photo by China Photos/Getty Images)

Visitors to Salisbury Cathedral stop to look at Sean Henry's sculpture Standing Man (2007) currently being exhibited in the Cloisters on August 2, 2011 in Salisbury, United Kingdom. The exhibition, “Conflux: A Union of the Sacred and the Anonymous”, features over 20 contemporary sculptures of dramatically different scales occupying vacant plinths and open spaces on both the inside and exterior of the iconic 13th century building. This exhibition brings to the Cathedral the biggest single group of polychrome sculpture since the Reformation and runs until the end of October. (Photo by Matt Cardy/Getty Images)

New York Police Department tactical police officers stand guard near the New York Stock Exchange on September 9, 2011 in New York City. Officials are stepping up security in New York and Washington D.C. a day after U.S. officials received a credible but unconfirmed terror threat to utilize car bombs on bridges or tunnels in New York or Washington. (Photo by Justin Sullivan/Getty Images)

A man impersonating North Korean leader Kim Jong Un gestures as he stands before North Korean cheerleaders attending the Unified Korean ice hockey game against Japan during the Pyeongchang 2018 Winter Olympic Games at the Kwandong Hockey Centre in Gangneung on February 14, 2018. (Photo by Yelim Lee/AFP Photo)

British Prime Minister Boris Johnson visits the Pavegen stand, a company that converts footsteps into energy, at the Innovation Zone during the UK-Africa Investment Summit in London, Britain on January 20, 2020. (Photo by Leon Neal/Pool via Reuters)