"The successful elimination of Mustafa Haji Mohamed was the action of the mujahedeen who are committed to killing all MPs," a Shebab official who asked not to be named told AFP, saying the group would "kill one-by-one" the country's remaining 274 lawmakers.
Mustaf Haji Mohamed, the father-in-law of former president Sharif Sheikh Ahmed, was gunned down on Saturday after leaving a mosque in Mogadishu, the first lawmaker to be targeted since the new assembly was selected in August.
Somalia's new President Hassan Sheikh Mohamud survived an assassination bid on September 12, just two days after he was elected, when apparent suicide bomb attacks claimed by the Islamist rebels rocked a Mogadishu hotel.
After more than two decades of war, Mogadishu has been coming back to life since the Shebab left frontline fighting positions, with a boom in building and business.
However, the Shebab have switched to guerrilla attacks -- including suicide bombings -- and remain a potent threat.
