SANAA (Reuters) - Thousands fled Sanaa on Saturday a day after President Ali Abdullah Saleh was wounded in an attack on his compound that marked a new stage in fighting which has brought Yemen closer to civil war.
Saleh's forces retaliated by shelling the homes of the leaders of a powerful tribal federation fighting an urban battle to oust Saleh.
The clashes have killed nearly 200 people over the last two weeks and turned areas of Sanaa into ghost towns after residents fled for safety.
Global powers are worried that Yemen, home to al Qaeda in the Arabian Peninsula (AQAP) and bordering the world's biggest oil exporter Saudi Arabia, could become a failed state, raising risks for regional security and Gulf oil shipments.
Several officials injured in the palace attack, including the speakers of both houses and parliament and the deputy prime minister were flown to Saudi Arabia for treatment, a medical source said without offering details on their condition.
Several officials were injured and seven killed when shells hit a mosque in the presidential palace, state media said. A senior diplomat said the prime minister, his deputy, the parliament speaker and other aides were hurt in the attack.
Saleh, a tenacious political survivor who has clung to power for nearly 33 years, said in an audio address late on Friday that an "outlaw gang" was behind the attack, which he blamed on the Hashed tribe led by Sadeq al-Ahmar. A tribal spokesman denied responsibility.
"I salute our armed forces and the security forces for standing up firmly to confront this challenge by an outlaw gang that has nothing to do with the so-called youth revolution," Saleh said. "Seven officers were martyred."
The deputy information minister said that Saleh, 69, had suffered minor injuries but was in good health. The president has not been seen in public since the attack.
Intermittent blasts and sporadic fire fights with automatic weapons punctuated the predawn hours in Sanaa and roads were clogged when the sun rose by civilians trying to flee the fighting that has engulfed more parts of the city.
"Bullets are everywhere, explosions terrified us. There's no chance to stay anymore," said Sanaa resident Ali Ahmed.
Nearly 400 people have been killed since a popular uprising against Saleh began in January, inspired by the movements in Tunisia and Egypt that toppled their long-standing leaders.
The battles are being fought on several fronts, with popular protests in several cities and military units breaking away from Saleh to protect the protesters.
There has also been a nearly week-long campaign in Zinjibar by locals and Saleh's soldiers to oust Islamist and al Qaeda militants who seized the southern coastal city near a shipping lane where about 3 million barrels of oil pass daily.
Saleh has exasperated his former U.S. and Saudi allies who had once seen him as a key partner in efforts to combat al Qaeda in the Arabian Peninsula (AQAP).
Defying world pressure, Saleh has thrice reneged on a deal brokered by Gulf states for him to quit in return for immunity from prosecution, even as he loses support at home.
(Additional reporting by Mohammed al-Ramahi in Sanaa, Mohammed Mukhashaf in Aden, Khaled al-Mahdi in Taiz, Mahmoud Habboush and Jon Herskovitz in Dubai and Samia Nakhoul in London; writing by Jon Herskovitz and Tim Pearce; Editing by Myra MacDonald)