In one of the bloodiest days of Yemen's uprising, government troops attacked a square full of protesters Saturday and battled with pro-opposition forces in the capital, killing 40 people.
The violence signaled an accelerated attempt by President Ali Abdullah Saleh and his loyalists to crush their rivals and tighten his grip on the country after his return Friday from Saudi Arabia, where he has been undergoing treatment for the past three months for wounds suffered in an assassination attempt.
One of his top rivals, Maj. Gen. Ali Mohsen al-Ahmar, called for international help, asking the United States and other regional powers to rein in Saleh. He warned that Saleh is pushing the country into civil war and compared him to the Roman emperor Nero, burning down his own city.
"With his return, Yemen is experiencing sweeping chaos and the harbingers of a crushing civil war, which this ignorant man is determined to ignite," said al-Ahmar, who was once a close ally of Saleh but early on in the uprising joined the opposition, along with the 1st Armored Division he commands.
Sanaa has become a city divided between rival gunmen, with barracks and roadblocks manned by men in different uniforms indicating their loyalties. The streets have become too dangerous for the residents to venture out. Many took cover in basements because of the fighting that has killed 140 people the past week.
The turmoil is a blow to U.S. efforts to find a stable transfer of power to ensure the continued fight against al-Qaida militants in Yemen, who Washington says constitute the most dangerous branch of the terror network. With the country spiraling deeper into disorder, al-Qaida-linked militants have already seized control of towns in southern Yemen beyond their traditional strongholds.
Saleh, who has clung to power despite nearly eight months of protests and the June 3 assassination attempt, abruptly returned to Yemen on Friday. Street battles that reignited a week earlier in Sanaa rapidly escalated, widening to include the most determined attack by Saleh's forces on al-Ahmar's military units, anti-government tribesmen and unarmed protesters.
Regime forces Saturday pounded the protest camp in Sanaa's Change Square where thousands were massed. Mortar shells exploded in the square, setting tents on fire. Snipers on nearby rooftops fired down on protesters dashing for cover.
Republican Guard troops and Central Security forces, led by Saleh's son Ahmed, fired anti-aircraft guns and rocket-propelled grenades down streets near the square in battles with soldiers loyal to al-Ahmar protecting the protesters.
At least 28 protesters and one of the soldiers guarding them were killed Saturday, and 54 people were wounded, said Mohammed al-Qabati, a medic at a field hospital in the square.
In northwest Sanaa, mortar shells rained down on the headquarters of Al-Ahmar's 1st Armored Division, killing 11 troops and wounding 112, according to a spokesman for the soldiers.
An official in al-Ahmar's office said his troops will remain on the defensive and won't go after Saleh's troops. The official said al-Ahmar conveyed the message to diplomats in Sanaa, who are apparently trying to contain the violence.
If al-Ahmar were to go on the offensive and move directly against Saleh and his leadership, that would likely escalate the violence. In his statement, al-Ahmar called on neighboring Gulf countries, the United States and the international community to deter Saleh, "stop his irresponsible behavior that aims to ignite a civil war that would have repercussions on the whole region."