Metropolitan Police officers prepare to carry out a raid on a property on the Churchill Gardens estate in Pimlico during Operation Woodstock on August 11, 2011 in London, England. Over 1,000 people have been arrested since the rioting began on Saturday and Police have started to raid properties across the capital as they round up people suspected of involvement in the rioting and recover stolen property. (Photo by Anthony Devlin - WPA Pool/Getty Images)

Gina Labianca (L) tries on a super woman outfit as Charlie Lucas tries a snow white Costume at the Halloween MegaStore Miami Beach on October 21, 2011 in Miami Beach, Florida. The megastore is a temporary location for the store which opened for the holiday to sell costumes, masks and other items to people needing to dress up for the evening of October 31 when costumed people around the world observe the day. (Photo by Joe Raedle/Getty Images)

Wakhi nomad women milk yaks in Wakhan, Afghanistan. About 12,000 villagers live at an altitude of 4,500 metres in the harsh, desolate terrain. The Wakhi people live a simple, relaxed life with their livestock. (Photo by Eric Lafforgue/Barcroft Images)

People ride bicycles in Halloween costumes during “Bike Kill 13” in the Brooklyn borough of New York City, October 29, 2016. “Bike Kill” is an annual gathering of builders and riders of home-made bicycles that culminates in a tall bike jousting competition. (Photo by Stephanie Keith/Reuters)

People take part in a Halloween street party at Lan Kwai Fong on October 31, 2016 in Hong Kong. Halloween, a contraction of All Hallows' Evening, falls on the day before All Saints' Day on November 1, a holiday when Christians remember their deceased loved ones. (Photo by Lam Yik Fei/Getty Images)

A picture shows the blood stained floor of a kindergarten following reported shelling in the rebel-held area of Harasta, on the northeastern outskirts of the capital Damascus, on November 6, 2016. At least four children were killed and 19 people injured in the government strike in Harasta, according to the Syrian Observatory for Human Rights. (Photo by Sameer Al-Doumy/AFP Photo)

A group of people wearing Santa Claus hats and swimming suits participate in the 13th charity Great Santa Claus Run in downtown Budapest, Hungary, Sunday, December 11, 2016. (Photo by Balazs Mohai/MTI via AP Photo)

People in traditional costumes prepare before competing in the 55th Verdiales music contest in Malaga, southern Spain December 28, 2016. Verdiales is a form of traditional Flamenco music, which is common in the province of Malaga. Members of singing groups, known as “pandas”, wear traditional costumes decked with flowers and other accessories as they perform in the contest, which is held annually on December 28. (Photo by Jon Nazca/Reuters)