ADEN (Reuters) - Missiles hit areas of Marib city in Yemen on Sunday, killing three civilians, a medical source and one resident said, at a time when the Iran-aligned Houthi movement is pressing ahead with an offensive to seize the gas-rich region.

       Residents said that two missiles targeted military areas but that a third landed near a residential district that houses the military headquarters of a Saudi Arabian-led coalition.

       (Reporting by Mohammed Ghobari; Writing by Ghaida Ghantous; Editing by Hugh Lawson)