Two more protesters were killed further south in Yemen`s flashpoint city of Taez, medics said.
"Twenty people, including two children and three soldiers from the First Armoured Brigade" were killed in Sanaa, a medic said, referring to a military unit headed by dissident General Ali Mohsen al-Ahmar.
The medics could not say where most of the bodies were arriving from but witnesses said security forces opened fire on protesters camping out at Al-Zubair Road, near to Change Square, the epicentre of anti-regime protests in Sanaa.
The protesters retaliated by throwing stones at the security forces, sparking fresh bursts of gunfire, the witnesses said.
The children, identified as Anas and Louay al-Suaidi, were shot dead by snipers as they travelled by car with their parents on a road west of Change Square, their mother said.
"My 10-month-old boy Anas was killed on my lap. He and his 10-year-old brother are martyrs," she said.
"I call on the people of the Arab Gulf and their regimes protecting him to look at what Saleh the criminal is doing to us," she said referring to Yemen`s President Ali Abdullah Saleh.
Protesters on Sunday marched towards central Sanaa provoking security forces to open fire in an attempt to drive them away from Al-Zubair Road, which is close to the office of Saleh`s son Ahmed, commander of the elite Republican Guard units.
Ahmar`s troops, protecting protesters since March, exchanged fire with security forces Monday and brought reinforcements to help protect demonstrators who had spent the night camped in central Sanaa, witnesses said.
They also besieged snipers deployed on one of the buildings in the same road, witnesses said.
Sunday clashes have left 26 people dead and hundreds wounded, according to medics. (*)
Editor: Kunto Wibisono
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