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)

People ride a motorcycle near Koudoukou Mosque where Pope Francis meets Imam Tidiani Moussa Naibi in Bangui, Central African Republic, November 30, 2015. (Photo by Stefano Rellandini/Reuters)

Aerobatic aircrafts fly during a performance at the Airshow Zhengzhou 2017 in Zhengzhou, capital of central China's Henan Province on April 27, 2017. The 5-day air show kicked off in Zhengzhou on Thursday, aiming to build a general aviation gathering center for business and communications. (Photo by Li An/Xinhua via ZUMA Wire)

Ariel Almiron and Alumine Deluchi compete in the final round of the Tango World Championship stage category, in Buenos Aires, Argentina, Saturday, September 25, 2021. (Photo by Natacha Pisarenko/AP Photo)

Devotees wearing full body costumes to resemble Hindu monkey god – lord Hanuman take part in a procession in Amritsar on February 13, 2023. (Photo by Narinder Nanu/AFP Photo)

People pass by the floating restaurant “Silver Whale” which partially sank during ice drift on the Neva River in St. Petersburg, Russia, 27 March 2023. Rescuers try to secure it with ropes so that the restaurant is not swept away by the river. The temperatures have reached zero degrees Celsius in the second largest city of Russia. (Photo by Anatoly Maltsev/EPA/EFE/Rex Features/Shutterstock)

A girl wearing a Santa hat surfs at Bondi Beach on December 25, 2019 in Sydney, Australia. December is one of the hottest months of the year across Australia, with Christmas Day traditionally involving a trip to the beach and celebrations outdoors. (Photo by Mark Evans/Getty Images)

Buddhist believers wearing faces masks to help protect against the spread of the new coronavirus wait to attend a service to pray for overcoming the COVID-19 outbreak and to celebrate Buddha's birthday at the Chogyesa temple in Seoul, South Korea, Thursday, April 30, 2020. (Photo by Ahn Young-joon/AP Photo)