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 woman takes a selfie next to a model of Thor during the Middle East Film & Comic Con (MEFCC) in Dubai, United Arab Emirates, Saturday, April 11, 2015. (Photo by Kamran Jebreili/AP Photo)

An India Christian devotee reenacts the sufferings of Jesus Christ on the occasion of Good Friday in Mumbai, India, Friday, March 29, 2013. Christians all over the world are marking Good Friday, the day when Christ was crucified. (Photo by Rajanish Kakade/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)

A dog at the Zoozashchita-NN veterinary clinic in Nizhny Novgorod, Russia on February 19, 2021. On February 13, 13 stray dogs with bright blue fur were found and caught at the Dzerzhinskoye Steklo (Dzerzhinsk Glass) factory producing acrylic glass and prussic acid in the city of Dzerzhinsk. The dogs' fur tested positive for the Prussian blue pigment; now the dogs are under supervision at the Zoozashchita-NN vet clinic in Nizhny Novgorod. (Photo by Mikhail Solunin/TASS)

Camels kick up clouds of sand as they race down a steep dune. The camels can reach speeds of up to 40 kilometres per hour as they descend the ten-metre tall dunes on April 20, 2022. The photos were taken by photographer Qian Guo in Naiman Banner, near the city of Tongliao in the Inner Mongolia region of northeastern China. The 58 year old said: “These are local Mongolian farmers, and two of them are a father and a son. They have more than ten camels which they farm and train”. (Photo by Qian Guo/Solent News & Photo Agency)

The Hindus of Nusa Penida, Bali, Indonesia, carry out their annual Ngaben cremation on April 4, 2022, when they place the bones of those who have died over the past year on to floating animal forms in a ceremony that is said to release the souls of the deceased. (Photo by Gede Sudika/Solent News/Rex Features/Shutterstock)

People walk behind the Medusa head in the Basilica Cistern in Istanbul, Turkey, 24 July 2022. The site has been restored by the Istanbul Metropolitan Municipality and is now open for visitors again. The Byzantine structure was commissioned by Emperor Justinian and built in 532. The underground Basilica, also called Underground Cistern, is the largest well preserved cistern in Istanbul, which rests on a total of 336 columns. According to historical texts, more than 7,000 slaves were involved in the construction of the cistern. (Photo by Sedat Suna/EPA/EFE)