A pig's head is seen in a basin after it was slaughtered it in the village of Azerany, Belarus, December 12, 2015. (Photo by Vasily Fedosenko/Reuters)

Damaged buildings are pictured at night in Aleppo, Syria December 11, 2015. (Photo by Ammar Abdullah/Reuters)

Passengers travel on the London train and underground system during the Christmas party season, December 18, 2015. (Photo by Paul Hackett/Reuters)

People take photos with the skyline of the central business district in Singapore on September 10, 2015. (Photo by Edgar Su/Reuters)

A reveller walks through the streets in the early hours during traditional May Day celebrations in Oxford, Britain, May 1, 2015. (Photo by Dylan Martinez/Reuters)

Labourers work at the installation site of Liquefied Petroleum Gas (LPG) pipeline on May Day or Labour Day in Chandigarh, India, May 1, 2015. (Photo by Ajay Verma/Reuters)

Women look at a collapsed building caused by earthquakes, in Bhaktapur, Nepal, May 18, 2015. Nepal is facing billions in reconstruction costs with almost 745,600 buildings and homes damaged or destroyed, including at least 87,700 in the capital, according to Nepal's emergency authority. (Photo by Ahmad Masood/Reuters)

Activists from People for the Ethical Treatment of Animals (PETA) promoting a vegan diet are pictured as people drive past in Los Angeles, California May 21, 2015. (Photo by Mario Anzuoni/Reuters)