Yemeni Protesters A Yemeni security official and two companions were killed and seven wounded in a Friday ambush by opposition tribesmen in Taez, south of Sanaa, a security source said, as shelling wounded four people .
In addition to Colonel Ahmed Rezaz and the two others, witnesses said four armed tribesmen and three civilians were wounded in the ambush in the Sharab al-Rona area of Taez.
Meanwhile, tribal sources said at least four people were wounded by shelling in northern Taez by Yemen\'s Republican Guards during clashes with opposition tribesmen.
The fighting broke out on Thursday night between the Guards, loyal to President Ali Abdullah Saleh, and tribesmen, allied with demonstrators who have since January been calling for him to quit, the tribal sources said.
The shelling was especially focused on Al-Rawda and Osaifra neighbourhoods and continued until Friday morning.
Witnesses said there was widespread panic.
Anti-regime activists have appealed for protests under the slogan \"Friday of a Civil State,\" after a call from influential cleric Sheikh Abdel Majid al-Zindani for the establishment of an Islamic state.
Meanwhile, Saleh supporters have called for demonstrations of \"Thanks and gratitude to the Custodian of the Two Holy Mosques,\" in reference to King Abdullah of Saudi Arabia, where Saleh has been hospitalised for more than a month after being wounded in a bomb attack on his palace.