Death toll among anti-government protesters from overnight clashes with Yemeni security forces in the southern province of Taiz rose Monday to at least 28 dead and up to 600 others injured, doctors told Xinhua.

Earlier the day, a doctor at the makeshift hospital in downtown Taiz said "there were 14 bodies of protesters lay in the makeshift hospital and hundreds of others are receiving treatment for injuries of gunshots, knifes, batons and tear gas after the security forces and armed government backers broke into the sit-in square following a 10-hour attack overnight."

He said that many people who were seriously injured were sent to private hospitals and the death toll was expected to increase.

Human rights activists said the security forces have arrested tens of protesters during overnight raid.

Meanwhile, witnesses said the armed government supporters set the tents of the protesters on fire as the security forces were now stationed in the square after they dispersed the protesters at dawn.

Since February, Yemen's major cities have faced almost daily clashes between police forces and anti-government protesters who demand an end to the 33-year rule of President Ali Abdullah Saleh.

The impoverished Arab country is trying to cement a ceasefire to end a recent tribe rebellion in the capital Sanaa that killed at least 127 people, as government forces have been shelling militants of the Yemen-based al-Qaida wing after the latter took over the southern troubled province of Abyan on Saturday.