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)

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

In this photo taken on Saturday, January 26, 2019 photo, rescued flamingo chicks have access to water at a centre after being rescued from a dried out dam in Kimberley, South Africa. A special airlift for thousands of baby flamingos is under way in South Africa as drought has put their breeding ground in peril. A reservoir that hosts one of southern Africa's largest flamingo populations is drying up. (Photo by AP Photo/Stringer)

Iranian chess player Sara Khadem competes, without wearing a hijab, in FIDE World Rapid and Blitz Chess Championships in Almaty, Kazakhstan December 26, 2022, in this picture obtained by Reuters on December 27, 2022. (Photo by Lennart Ootes/FIDE/via Reuters)

A child gets his head shaved by a Buddhist monk during a ceremony to prepare children to live as Buddhist monks for three weeks at Jogyesa Temple on May 09, 2023 in Seoul, South Korea. As part of the celebration of Buddha's birthday, young children are annually invited to become Buddhist monks for a three-week period. (Photo by Chung Sung-Jun/Getty Images)

Belarus' Aryna Sabalenka in action against Karolina Muchova at Roland Garros Grand Slam Tournament – Day 12 on June 08, 2023 in Paris, France. (Photo by Lisi Niesner/Reuters)

This photo taken on October 30, 2022 shows people in costumes walking on the street during a celebration ahead of Halloween in Guangzhou in China's southern Guangdong province. (Photo by AFP Photo/China Stringer Network)