Fifteen people were detained in Dali, where protestors damaged shops and electricity poles, witnesses said, while security forces detained dozens after raids in the southern town of Loder.

Security forces dispersed two demonstrations in al-Dali, south of the capital Sanaa, and the nearby town of al-Habilayn, witnesses told AFP.

Heavy army presence

President Ali Abdullah Saleh pledged on Saturday to pursue all those responsible for "the destructive acts ... who will be tried".

Army and police forces remained deployed in the capital and other major cities and towns where clashes between security forces and demonstrators over the past two days left at least 30 dead.

Opposition parties criticised the 
destruction of property 

Government forces, backed by army tanks and armoured vehicles, were deployed on main crossings and around official buildings, many of which suffered damage during the riots.

Meanwhile, armed tribesmen held on to more than 60 gas tankers they seized in Maarib, east of Sanaa, to prevent them from reaching the capital where the shortage has already raised gas prices, witnesses said.

Price increases

The Yemeni cabinet announced late on Tuesday that it had decided to remove subsidies on fuel, nearly doubling petrol prices from 35 rials a litre to 65 rials while diesel jumped from 17 rials to 45 rials.

Opposition parties called for the government to reverse the
price rise.

They criticised "acts of vandalism" by protesters but also condemned the "killings in confronting the public outcry against government measures" and called for an independent investigation into the deaths.

Yemen, at the southeastern tip of the Arabian peninsula, has a population of 19.7 million and per capita gross domestic product is less than $800. 

Clashes often break out in Yemen, a country with a tribal structure where the number of firearms in civilian hands is officially estimated at more than 60 million, or more than three per inhabitant.