Yemeni security forces shot dead three more protesters against President Ali Abdullah Saleh on Monday while opposition politicians debated whether to cooperate with a Gulf plan for the veteran autocrat to step aside.
The risk of Yemen, the poorest Arab state long on the brink of collapse, descending further into bloodshed is a major worry for Saudi Arabia and the United States, which fear an active al Qaida wing could strengthen a foothold in the Arabian Peninsula.
Witnesses said security men opened fire to stop protesters marching through the city of Taiz, south of the capital. They were trying to join a pro-democracy rally that would take them past a palace belonging to Saleh.
"There were thousands in a march who came from outside Taiz, but the police, army and gunmen in civilian clothes confronted them, opening fire with bullets and tear gas," said Jamil Abdullah, a protest organiser.
"They opened fire heavily from every direction."