A bomb explosion on Wednesday in an open market in Yemen's oasis city of Marib killed seven people and wounded 18, security and medical sources said. The blast targeted a market selling qat, the mild narcotic leaf popular in the Arabian Peninsula country, a security official in Marib said. A medical source at the city's public hospital confirmed the toll. Forces loyal to President Abedrabbo Mansour Hadi control Marib, which is east of Yemen's rebel-held capital Sanaa.