Yemeni government opponents clashed with police Thursday in the southern province of Aden, as tens of thousands of protesters rallied nationwide to denounce a deadly government crackdown and demand the president's ouster.
The street clashes were triggered by a bomb attack by an unknown armed group on a checkpoint in the provincial capital, Krater, and signaled the rapid deterioration of security in Yemen, a nation that was already beset by poverty and armed conflict before the anti-government uprising that began in February.
"They threw the bomb at the checkpoint and the guards began to shoot randomly at the people," said opposition activist Adnan Abdel-Mohsen. Three Republican Guard troops were injured, he said.
The checkpoint was near the Aden branch of Yemen's central bank and on the road to the presidential palace, and a gunbattle broke out that lasted through the night.
Abdel-Mohsen said there was little police presence in the streets of Krater and that gunshots were heard ringing through different parts of the city. Many police and security troops have abandoned their posts during the uprising.
"We blame the government for allowing this chaos to happen," Abdel-Mohsen said. "We demand the police come back to the street to control the situation and protect us."
President Ali Abdullah Saleh, who has ruled over Yemen for 32 years, has refused to step down. Massive protests and defections by military commanders, ruling party members and other one-time allies have left him clinging to power with the help of loyal military units commanded by one of his sons and other relatives.
On Thursday, Saleh fired the country's prosecutor general, Adullah al-Olofi, state TV reported. The prosecutor had refused to blame opposition youth for violence in the capital a day earlier.
Security forces backed by snipers on rooftops, fired on demonstrators in Sanaa, killing 12 and wounding nearly 200.
Protesters turned out Thursday to denounce the killings, which resembled a March 18 sniper attack in Sanaa that killed more than 40 and prompted the wave of defections among Saleh's allies to the opposition.
Opposition parties said in a statement that Wednesday's killings were a "savage massacre" and constituted a crime against humanity by Saleh and members of his family who head special branches of the military that they accused of firing on the protesters.
U.N. Secretary-General Ban Ki-moon expressed concern at Wednesday's violent clashes and called on Yemeni authorities "to uphold their responsibility to protect civilians and abide by international human rights obligations," U.N. spokesman Martin Nesirky said.
The U.N. chief welcomed efforts to promote a peaceful transition, appealed for restraint and emphasized "that broadly inclusive political dialogue and mutual understanding are critically important for overcoming the current crisis and preserving the country's unity and integrity," Nesirky said.
Meanwhile, foreign ministers of the six-nation Gulf Cooperation Council will meet Sunday in the Saudi capital, Riyadh, to fine-tune a draft proposal, accepted by Saleh and the established opposition political parties, for ending Yemen's crisis. The proposal calls for the creation of national unity government and would have Saleh transfer power to his vice president within 30 days of the signing of the deal.
In exchange, Saleh and his family would receive immunity from prosecution.
The street protesters, which say the opposition parties do not represent them, have rejected the GCC plan, insisting that Saleh must immediately step down and that he and his sons be prosecuted for the violence against protesters.
The opposition parties warned they might not sign the agreement if the killings continued.
"Without securing the protection of peaceful protesters, we will not find ourselves able to sign the agreement," they said in the statement, warning that killing protesters would not help Saleh remain in power.
Maj. Gen. Ali Mohsen al-Ahmar, commander of the 1st Armored Division, who joined the uprising last month and deployed his units to defend the Sanaa protesters, called on "all honest people" to rise up against what he called the killers of the regime.
He denounced Wednesday's killings and said in a statement that Saleh was trying to sow divisions within the armed forces. Al-Ahmar was the most senior army commander to defect to the side of the protesters. Others included lawmakers, politicians, Cabinet ministers, policemen and diplomats.