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)

The Invasion. A quiet street in Macau. Modernization around is quickly changing the city, as documented by Paul Tsui. (Photo by Paul Tsui/National Geographic Travel Photographer of the Year Contest)

A participant, surrounded by red chilli peppers, takes part in a chilli-eating competition at a hot spring in Yichun, Jiangxi province, China on December 9, 2018. (Photo by Chen Fei/China News Service via Reuters)

People pose for photos in the snow in the Manhattan borough of New York City, New York, U.S., December 2, 2019. (Photo by Carlo Allegri/Reuters)

Monkeys sit along a street during a snowfall in Ayubia, some 75 km north of Islamabad, Pakistan on January 7, 2020. (Photo by Aamir Qureshi/AFP Photo)

National Police members disinfect Venezuelan citizens returning to the country from Colombia, as a preventive measure against the spread of the coronavirus –COVID19- at the Simon Boliviar International Bridge, in Cucuta, Colombia-Venezuela border, on April 4, 2020. Since the first case of COVID-19 was detected last March 6, Colombia has reported 1,406 people infected and 32 dead. (Photo by Schneyder Mendoza/AFP Photo)

A municipality worker in a protective suit feeds street cats at Sultanahmet Square, as the spread of coronavirus disease (COVID-19) continues in Istanbul, Turkey, April 9, 2020. (Photo by Umit Bektas/Reuters)

People walk along Beachy Head, close to Eastbourne on the south coast of England on April 12, 2020, as life in Britain continues over the Easter break, during the nationwide lockdown to combat the novel coronavirus pandemic. Britain's Prime Minister Boris Johnson was making “very good progress” on Saturday in his recovery in hospital from coronavirus, officials said, as the country's deaths toll from the disease approached the grim milestone of 10,000. (Photo by Ben Stansall/AFP Photo)