Security forces clashed on Wednesday in Yemen’s third largest city of Taiz with followers of the opposition, which is seeking the overthrow of President Ali Abdullah Saleh.
Seven people were wounded in the violence, witnesses said.
On-and-off clashes between government forces and armed tribesmen who appointed themselves to defend protesters have paralysed Taiz, 200 km (120 miles) south of Sanaa, and other protest hubs. Yemen is entering its sixth month of mass protests calling for an end to Saleh’s three-decade rule.
Security forces fired shots into the air to disperse 5,000 protesters who marched near Republican Guard barracks chanting anti-Saleh slogans and rallying against Saudi and American interference in Yemeni affairs.
Pro-opposition tribesmen responded by shooting in the air.
Neighbouring Saudi Arabia and the United States have been trying to end Yemen’s political stalemate, fearing growing chaos could strengthen al Qaeda’s regional, Yemen-based wing.
Saleh has backed out three times from a Gulf-brokered plan to ease him from power. He is in Saudi Arabia recovering from injuries sustained in a bomb attack at his Sanaa presidential palace in early June.
Further south, tribesmen launched an offensive against Islamist militants in Abyan province, who have taken over two major cities in recent months and are threatening an already weak military grip on the area.
“We are defending our land, and the militants have overstepped their bounds … We will kill them wherever they are found,” a southern tribal leader told Reuters, adding they had cut supply lines to the city of Zinjibar, which was seized by militants in May.
Opponents of Saleh accuse him of deliberately letting militants gain a foothold in the south to convince Western powers and Saudi Arabia only he stands in the way of a militant Islamist takeover.