Police have arrested 16 members of the militant wing of an Islamic group ruling much of southern Somalia for six months last year.
Somalia's government has been trying to wipe out the remnants of the Council of Islamic Courts, who have vowed to launch an Iraq-style insurgency until the country becomes an Islamic state. The courts and particularly the group's militant wing, the Shabab have been accused of links to al-Qaida.
"We know these elements belong to the Shabab and are behind suicide bombings and explosions in the capital," Mogadishu Mayor Mohamed Dheere told The Associated Press. "We will continue to crack down all terrorist elements."
Dheere also said police confiscated "large quantities of arms."
Somalia has been mired in chaos since 1991, when warlords overthrew dictator Mohamed Siad Barre and then turned against each other. The current administration, called the Transitional Federal Government, was established in 2004 with U.N. backing, but has struggled to assert control.
Aden Hashi Ayro, a Somali trained in al-Qaida camps in Afghanistan before 2001, is on the U.S. State Department's list of suspected terrorists and remains the overall leader of the Shabab.