Forces loyal to the embattled Yemeni president killed 20 protesters as they dispersed a sit-in in Taez, an organizer said on Monday.
Security service agents backed by army and Republican Guard troops stormed the protest against President Ali Abdullah Saleh in Freedom Square in the centre of Yemen's second-largest city during the night, shooting at the demonstrators and setting fire to their tents, protesters said.
"At least 20 protesters have been killed," one of the protest organizers said.
Troops backed by tanks stormed a field hospital and detained 37 of the wounded receiving treatment there, among hundreds of people rounded up as security forces pursued the protesters into nearby streets, medics and organizers said.
"This was a massacre. The situation is miserable. They have dragged the wounded off to detention centers from the streets," activist Bushra al-Maqtari told AFP.
Protesters said that the square had been entirely cleared, while security forces stormed a nearby hotel and arrested several journalists.
The Common Forum opposition coalition condemned the "crimes against humanity" committed by Saleh's "remaining military and security forces and armed militias."
It warned the veteran president he would be "held personally responsible for his continued crimes against the people."
"These crimes do not get forgotten with time. They are being monitored and documented, and those who have committed them, and who provided arms and money, will not escape justice."
The four-month-old sit-in in Taez was the longest-running protest against Saleh's rule.
The clashes erupted on Sunday evening outside a nearby police station as some 3,000 people gathered to demand the release of a detained protester.
Police fired warning shots then fired into the crowd when the demonstrators refused to leave, a local committee of the "Youth of the Revolution" group said.
On March 18, 52 people died when regime loyalists attempted to break up a similar protest against Saleh's rule in University Square in the capital Sanaa. The president declared a state of emergency after the bloodshed.
More than 200 demonstrators have been killed since the protests first erupted in Yemen. Scores more have died in armed clashes between loyalist troops and dissident tribesmen.
The opposition grouping signed up to a deal brokered by impoverished Yemen's wealthy Gulf neighbors under which Saleh, in power since 1978, would hand power to the vice president within 30 days in return for a promise of immunity from prosecution.
The president initially agreed to the plan but then repeatedly set new conditions for signing it, prompting the six-nation Gulf Cooperation Council to suspend its mediation efforts.
PHOTO CAPTION
Yemeni anti-government protesters carry a wounded comrade following clashes with security forces in Yemen's second-largest city of Taez (Taiz), south of Sanaa, late on Sunday, 29, 2011.
Source: AFP