At least 46 people have been killed after a fresh wave of protests in the Yemeni capital Sanaa.
Demonstrators against President Ali Abdullah Saleh came under fire from pro-regime forces, as they took to the streets on Sunday and again on Monday.
It is the bloodiest assault Sanaa has seen for months, escalating violence that has shattered an uneasy stalemate.
Government forces are said to have opened fire on Sunday with anti-aircraft guns and automatic weapons
On Monday, snipers launched their attacks from rooftops.
“All the urban areas and border areas of Sanaa are now under the control of Saleh’s forces. They attacked local residents and our supporters,” an opposition soldier said.
The UN has urged the Yemeni government to stop using force against those demonstrating.
President Saleh refuses to hand over power and is currently in neighbouring Saudi Arabia, recovering from an assassination attempt in June.