An Iraqi soldier stands guard as a pipeline burns in the background after an explosion 30 kilometers (20 miles) northeast of Tikrit, Iraq, Monday, February 11, 2008. (Photo by Bassem Daham/AP Photo)

A member of the Community Police of the FUSDEG (United Front for the Security and Development of the State of Guerrero) search for a man, who ran away upon seeing the Community Police approach as they patrolled a street, in the village of Petaquillas, on the outskirts of Chilpancingo, in the Mexican state of Guerrero, February 1, 2015. Approximately 500 members of the Community Police from the FUSDEG took control of the security of the village of Petaquillas on the night of January 30 at the request of the people tired of the actions of organized crime, local media reported. (Photo by Jorge Dan Lopez/Reuters)

A picture made available on 07 March 2016 shows visitors petting and holding a Fennec fox, native to the Sahara, in the petting room at the Little Zoo Cafe, a business built to capitalize on Thais' love for exotic animals, and food, on the outskirts of Bangkok, Thailand, 05 March 2016. The cafe boasts Fennec foxes, Meerkat, native to parts of Africa, Silver Fox, Raccoon and Chinchillas, along with a menu of Thai food and Cheesecake, among other sweet deserts. Nature is a faraway fantasy in the bustling exhaust-filled cement city of Bangkok, fuelling a demand to own and be close to exotic pets. The trend to be near to a species that was once wild, in a city environment, far from the natural setting, has drawn criticism but continues to grow. (Photo by Barbara Walton/EPA)

Refugee children play with a stuffed toy at a muddy makeshift camp at the Greek-Macedonian border, near the village of Idomeni, Greece March 15, 2016. (Photo by Alexandros Avramidis/Reuters)

An abandoned tank left by Boko Haram, February 20, 2016, seen on the road to Michika, Nigeria – a town formerly occupied by the insurgents. On April 14, 2014, 300 schoolgirls in the Chibok village in Nigeria were kidnapped by the terrorist group, Boko Haram. Two years later, the majority of these girls are still missing. According to the Global Terrorism Index Report 2015, Boko Haram, which operates mainly in Nigeria, has become the most deadly terrorist group in the world. (Photo by Danielle Villasana)

A police officer detains a woman on suspicion of collaborating with the 18th street gang during a "Safe House" operation at the Concepcion neighbourhood in San Salvador, July 2, 2015. Salvadoran police make “Safe House” operations at dangerous neighbourhoods of the capital to prevent murders, according to local media. (Photo by Jose Cabezas/Reuters)

People stroll alongside one of the hills of the Tio Pio park in Madrid, Monday, January 25, 2016. The park is a high viewpoint frequented mostly by locals due to its view of the Spanish capital skyline. (Photo by Francisco Seco/AP Photo)

South Korea's Black Eagles aerobatics team performs an aerial display forming a Ying and Yang logo during the Singapore Airshow at Changi exhibition center in Singapore on February 16, 2016. (Photo by Roslan Rahman/AFP Photo)