"On September 21, 2013, masked gunmen attacked the upscale Westgate shopping mall in Nairobi, Kenya, taking hostages and killing at least 67 people. Almost 200 people, including at least 5 U.S. citizens, were wounded in the siege, which lasted four days. The attack is the most deadly terrorist incident in Kenya since the 1998 Al Qaeda bombing of the U.S. embassy in Nairobi. A Somali Islamist insurgent group, Al Shabaab, which has ties to Al Qaeda, has claimed responsibility for the Westgate attack. Al Qaeda and affiliated groups like Al Shabaab have had a presence in East Africa for almost 20 years, although the extent of their operations there has varied over time. The region's porous borders, proximity to the Arabian Peninsula, weak law enforcement and judicial institutions, and pervasive corruption, combined with almost 20 years of state collapse in neighboring Somalia, have provided an enabling environment for violent extremist groups. […] In the 15 years since the embassy bombings in Kenya and Tanzania, Congress has appropriated increasing counterterrorism funding for Africa, and has focused hearings and investigations on reported support provided by U.S. citizens to Al Shabaab. The United States is a major contributor of financial and in-kind support to AMISOM [African Union Mission in Somalia], and has provided its troop contributors and other countries in the region with substantial support to counter terrorist threats. 'We are in this fight together,' the U.S. ambassador to Kenya commented as Federal Bureau of Investigation forensic teams deployed after the Westgate attack. President Obama has pledged U.S. support to bring those responsible for the attack to justice. Political instability and terrorist activities in and emanating from Somalia are subject to ongoing interest by policy makers, who remain concerned about Al Shabaab's ties to Al Qaeda and affiliated groups and its use of Somalia as a staging ground for attacks in the region and a training ground for foreign fighters. The following sections address possible questions about the attack and related issues for Congress."
CRS Report for Congress, R43245