United States Marines perform a fighting demonstration in Times Square as part of Fleet Week festivities May 27, 2011 in New York City. Fleet Week, which has been held in New York since 1984, brings thousands of military members to the city where they engage the public with numerous activities, demonstrations, tours and contests. Fleet Week concludes on Memorial Day with a military flyover to honor those killed while serving in the military. (Photo by Spencer Platt/Getty Images)

Boys pan for gold on a riverside at Iga Barriere, 25 km (15 miles) from Bunia, in the resource-rich Ituri region of eastern Congo February 16, 2009. Ituri is one of many areas of the country to have experienced bitter ethnic conflict between rival tribes in recent years. Massacres have left tens of thousands dead. It is this fighting that led U.S. authorities to take the unprecedented step of naming Congo in section 1502 of the Dodd-Frank financial regulation act, which says U.S.-listed companies that source gold, tungsten, tantalum and tin from Congo or its neighbours must assure the U.S. stock exchange regulator that their business is not helping fund conflict. (Photo by Finbarr O'Reilly/Reuters)

Pedestrians cover their face as they walk along the dusty road in Kathmandu, Nepal February 27, 2017. Nepal has forced 2,500 old vehicles off roads in its capital city of Kathmandu, part of a fight against alarming air pollution levels that have hit nine times World Health Organisation (WHO) limits. Air pollution has been a chronic problem in rapidly growing Kathmandu, which sits in a Himalayan valley and is home to more than 3mn people. (Photo by Navesh Chitrakar/Reuters)

A woman holds Kalashnikov assault rifle during a training session with members of the Georgian Legion, a paramilitary unit formed mainly by ethnic Georgian volunteers to fight against Russian forces in Ukraine in 2014, in Kyiv, Ukraine, Saturday, February 19, 2022. Separatist leaders in eastern Ukraine have ordered a full military mobilization amid growing fears in the West that Russia is planning to invade the neighboring country. The announcement on Saturday came amid a spike in violence along the line of contact between Ukrainian forces and the pro-Russia rebels in recent days. (Photo by Efrem Lukatsky/AP Photo)

A young girl makes a “tomato angel” on a tomato covered street during the traditional tomato fight “Tomatina” during the fiestas in Bunol, Spain, 28 August 2013. This year's Tomatina is the first pay festival after Bunol's City Hall sold 15,000 tickets to take part in the tomato throwing. A total of 20,000 people, including 5,000 residents, will throw over 130,000 kg tomatoes. Local authorities decided to sell tickets this year to avoid the overcrowding in previous years in which over 50,000 people took part in the event. (Photo by Biel Alino/EPA)

A Syrian boy is comforted as he cries next to the body of a relative who died in a reported airstrike on April 27, 2016 in the rebel-held neighbourhood of al-Soukour in the northern city of Aleppo. The Syrian army was preparing an offensive to retake the whole of Aleppo, as fighting in the divided second city killed 38 civilians in a new blow for a tattered truce. Nearly 200 people have been killed in Aleppo in the past week as rebels have pounded government-held neighbourhoods with rocket and artillery fire and the regime has hit rebel areas with air raids. (Photo by Karam Al-Masri/AFP Photo)

In this photo taken Saturday, February 14, 2015, Benjamin Miller, 20, from Georgia, in the US, is gored by a bull during the “Carnaval del Toro” in Ciudad Rodrigo, Spain. An American youth is recovering in the intensive-care unit of a hospital in western Salamanca after being savagely gored during a bullfighting festival celebrating Carnival, officials said Sunday. Surgeon Enrique Crespo said he was called to operate on 20-year-old Benjamin Miller from Georgia, who had been gored and tossed by a large fighting bull on Saturday, the first day of nearby Ciudad Rodrigo's “Carnaval del Toro”. (Photo by Jose Vicente/AP Photo)