Saudi Arabia led airstrikes against Shiite rebels in Yemen as it seeks to prop up an allied government facing the loss of its last remaining stronghold.

The Saudis headed a coalition of 10 Sunni-ruled nations that carried out raids around Yemen's capital Sanaa, which is controlled by the Houthi rebels. The attack came after the rebels advanced on the southern port of Aden, where forces loyal to President Abdurabuh Mansur Hadi had rallied. A new wave of bombings began late on Thursday, pounding army posts around the capital as anti-aircraft artillery fired back.

The coalition has no immediate plan to send ground troops to Yemen, though it's ready to do so if needed and plans to continue the air operation for as long as is necessary, Ahmed Asseri, a Saudi military officer and spokesman for the operation, said at a press conference in Riyadh.