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 man is silhouetted in front of the Allianz-Arena as he walks his dogs at sunrise in Munich, southern Germany, Friday, April 10, 2015. (Photo by Peter Kneffel/AP Photo/DPA)

Cemetery workers repaint tombs inside the municipal cemetery in Navotas city, north of Manila October 29, 2015. Filipinos are preparing to celebrate All Saints Day on November 1 by visiting the graves of their departed loved ones. (Photo by Ezra Acayan/Reuters)

A local boy plays football on Iracema Beach on June 11, 2014 in Fortaleza, Brazil. (Photo by Robert Cianflone/Getty Images)

An employee of the National Park Service takes a selfie with President Barack Obama, left, in the background meeting with the crowd after a tour of Everglades National Park on Earth Day, Wednesday, April 22, 2015, in Florida. Obama used the visit to warn of the damage that climate change is already inflicting on the nation's environmental treasures. (Photo by Lynne Sladky/AP Photo)

An instructor (C) adjusts the posture of students of flight attendant major during a training session at Anhui Foreign Languages University, in Hefei, Anhui province, China, May 25, 2015. (Photo by Reuters/China Daily)

Police officers speak to a woman in Greenwich Park in London, England on April 4, 2020. The Government has announced a lockdown to slow the spread of Coronavirus and reduce pressure on the NHS. (Photo by Alamy Live News)

An employee in protective gears sprays disinfectant at the main exhibition tank at the Sea World at Jaya Ancol Dream Park as it is closed for public in the wake of coronavirus outbreak in Jakarta, Indonesia, Saturday, March 14, 2020. Indonesia's capital city announced a lockdown of all tourist destinations and entertainment spots as well as the closing all of its public schools for the next 14 days amid the global outbreak. For most people, the new coronavirus causes only mild or moderate symptoms. For some it can cause more severe illness. (Photo by Dita Alangkara/AP Photo)