A commander of Somalia’s Islamic extremist rebels denounced said the country’s recent election of a new president and vowed to continue fighting the government, the first official comment from al-Shabab since the president’s election earlier this month. In an audio message released by al-Shabab’s radio arm Sunday, Sheikh Hassan Yaqub, a senior commander of the extremist group, called Somalia’s new president Mohamed Abdullahi Mohamed an “apostate” and warned Somalis against supporting him.