The respected leader of a Rainier Valley mosque was arrested Monday on an immigration charge, surprising those who knew his work in Seattle's Somali community. Federal agents with the Joint Terrorism Task Force arrested Abu Abrahim Sheik Mohamed at Sea-Tac Airport as he got off a domestic flight, federal criminal justice sources said. U.S. Immigration and Customs Enforcement spokeswoman Lorie Haley said only that Mohamed, 37, was "in custody on immigration violations" and is being held at the Northwest Detention Center in Tacoma. She declined to specify what immigration regulations Mohamed is accused of having violated. While he is being...