Yemeni security forces fired tank and artillery shells at a restive southern city on Friday, killing 14 people, including three women and a 9-year-old boy, a medical official said.
Violence has escalated in the Arab world's poorest country throughout a nearly nine-month popular uprising seeking to oust autocratic President Ali Abdullah Saleh after 30 years in power.
In Friday's bloodshed, troops from the Republican Guard, which is led by Saleh's son and is a pillar of his rule, shelled two neighborhoods in the southern city of Taiz and fired at protesters in the city's main square. Fourteen people were killed, said a medical official who spoke on condition of anonymity because he was not authorized to talk to reporters.
Taiz, a hotbed of the opposition, has been particularly violent recently, with government troops regularly clashing with soldiers who have defected and sided with the anti-Saleh protesters.
Anti-government tribesmen also attacked security positions there on Friday, killing two soldiers and wounding eight others, the Defense Ministry said. The military blamed the attack on Islamists and said three gunmen were killed in the clashes.
Security across the country has broken down and clashes between government forces and army units that have joined the uprising regularly shake Yemeni cities. In June, an attack on the presidential compound in the capital badly wounded Saleh and killed several of his bodyguards. He spent weeks being treated in Saudi Arabia.
In the country's south, al-Qaida-linked militants have taken over entire towns, raising Western fears they will have freer rein to use the area as a staging ground for international attacks.
With fighting escalating in Taiz, hospitals there are facing shortages of medicine and struggling to treat the wounded, the Yemen Observatory for Human Rights said in a statement. The rights group also said Saleh's forces have been arresting people in the city indiscriminately and holding them in unspecified locations.
For months, tens of thousands of demonstrators have held rallies each Friday in the capital, Sanaa, for and against the regime.
In one area on Friday, regime supporters chanted, "The people want Ali Abdullah Saleh" _ a variation of the chant "the people want to topple the regime" that became famous during the uprisings in Egypt and Tunisia.
In another Sanaa neighborhood, anti-government protesters called for Saleh to face trial for the bloody crackdown on protesters, which has killed hundreds and wounded thousands.
International diplomacy has failed to stop the crisis, with Saleh repeatedly refusing to sign a U.S.-backed proposal by Yemen's powerful Gulf neighbors that would grant him immunity from prosecution if he hands over power to his vice president.
The U.N. special adviser on Yemen, Jamal Benomar, was visiting the country to push for "efforts aimed at encouraging an inclusive transition process that meets the needs and aspirations of all Yemenis," U.N. spokesman Martin Nesirky said Thursday.