Four people were injured by security forces when tens of thousands of protesters marched through Taiz in southern Yemen calling for the ouster of the regime, dpa reported.
The demonstrators carried slogans such as "Military rule must end" and "Thugs out."
Gunfire erupted late Thursday after a breakdown in truce talks between Taiz security director Abdullah Qairan and the commander of the Republican Guards al-Awbali.
In the nearby governate of Abyan, 15 suspected al-Qaeda members were arrested, state news agency Saba reported Thursday.
In his most recent public appearance, President Ali Abdullah Saleh reasserted his commitment to a deal brokered by Gulf countries on a constitutional power transfer.