A Somali police officer arrests a suspected rebel member of the al Qaeda-affiliated al Shabaab among beach goers in Mogadishu. Al Shabaab claimed responsibility for today's pre-dawn attack on a Kenyan university campus near the Somali border. The following gallery examines who is al Shabaab. Here: Somali police officer (R) arrests a suspected rebel member (L) of the Al Qaeda-affiliated al Shabaab among beach goers at the Lido beach north of Somalia's capital Mogadishu March 23, 2012. (Photo by Feisal Omar/Reuters)

A family dressed in traditional chinese clothes celebrates the Chinese New Year in Chinatown in Bangkok, Thailand February 8, 2016. (Photo by Jorge Silva/Reuters)

People dressed as zombies participate in a parade for World Zombie Day 2016 in London's West End, Britain on October 9, 2016. (Photo by Splash News and Pictures)

Ukraine's Leonid Stadnyk, who stands at a height of 2.53 metres (eight feet four inches) and may be considered the world's tallest living man, near his house in the village of Podolyantsi in Ukraine's Zhytomyr region, about 200 km (124 miles) from the capital Kiev, 2005. (Photo by Reuters/Stringer)

Brazilian model Izabel Goulart for the screening of the film “Sink Or Swim (Le Grand Bain)” at the 71st Cannes Film Festival, France on May 13, 2018. (Photo by Stephane Mahe/Reuters)

This picture released by Turkish Cumhuriyet Daily newspaper shows Dilek Dundar (L), the wife of editor-in-chief of Turkish newspaper Cumhuriyet daily Can Dundar, trying to stop a gunman who is also being held back by a man on May 6, 2016 in Istanbul. Turkish opposition journalist Can Dundar escaped a shooting on May 5 outside a courthouse in Istanbul where he is on trial, adding police detained the assailant. Dundar, who was unharmed, was outside the courthouse during a break as the court prepared to deliver its verdict in his trial for allegedly revealing state secrets in a newspaper story. (Photo by AFP Photo/Cumhuriyet Daily Newspaper)

A Humboldt penguin stands on weighing scales whilst being photographed by members of the press during a photocall at the annual weigh-in at London Zoo in London, Britain, 24 August 2016. Every animal that is in the zoo is weighed and measured and the statistics recorded so the data can be shared with zoos across the world. (Photo by Hannah McKay/EPA)

An art installation formed with milk churns, made by land art artist Gerard Benoit a la Guillaume, is seen at the Chenau de Mayen in the resort of Leysin, Switzerland August 7, 2015. More than 80 milk churns were placed between the Tour d'Ai and the Tour de Mayen summits at an altitude of 2,000 meters (6,561 feet) above sea level under the direction of the artist, to be photographed for his ongoing art project entitled “Milk churns without borders”. (Photo by Denis Balibouse/Reuters)