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)

Russia's Ekaterina Birlova casts a shadow on the sand as she serves to Poland during a women's beach volleyball match at the 2016 Summer Olympics in Rio de Janeiro, Brazil, Tuesday, August 9, 2016. (Photo by Marcio Jose Sanchez/AP Photo)

Show promoters for Motolite batteries sit on a jeepney as they pose for photographers during the Manila International Auto show in Pasay, Metro Manila, Philippines on April 4, 2013. (Photo by Erik De Castro/Reuters)

Model Irina Shayk attends the screening of “Sorry Angel (Plaire, Aimer Et Courir Vite)” during the 71st annual Cannes Film Festival at Palais des Festivals on May 10, 2018 in Cannes, France. (Photo by George Pimentel/WireImage)

In this photograph taken on June 11, 2018, Chinese artists performs during a Indo-China cultural exchange program in Kolkata, West Bengal, India. (Photo by Dibyangshu Sarkar/AFP Photo)

Actor Mike Lane, standing six feet 10 inches in his stocking feet, makes a perfect monster as he carries actress Nancy Knox down the stairs into Frankenstein's dungeon, February 28, 1958. They have featured parts in the upcoming Boris Karloff movie “Frankenstein 1970”. (Photo by David F. Smith/AP Photo)

In this picture taken late on June 13, 2017, physiotherapist Masayuki Ozaki takes a bath with his silicone s*x doll Mayu at a love hotel in Yachimata, Chiba prefecture. Around 2,000 of the life- like dolls – which cost around 6,000 USD and come with adjustable fingers, removable head and life- like genitals – are sold each year in Japan, according to industry insiders. (Photo by Behrouz Mehri/AFP Photo)

Adolf Hitler (left), German Nazi politician, in a deck chair next to is niece Angela (Geli) Raubal – around 1930. (Photo by Ullstein Bild/Ullstein Bild via Getty Images)