Activists in Syria say government security forces this morning launched a fresh bombardment of the central city of Homs, with at least 12 people killed, Agence France Presse reported.
Dozens more people are said to be have been wounded in the attack, which began at dawn.
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Homs resident Omar Shaker told AFP that government troops were using rockets and artillery fire, describing the scenes as “beyond belief."
Abu Abdo Alhomsy, an activist in Homs, told Al Jazeera:
"It is horrible right here. Rockets are falling. There are massive explosions that shook buildings. We don't know really what to do … It’s a massive attack - a new massacre is happening here. Nobody can go out, we don't know how many homes have been hit or how many people died."
Today’s violence comes after the opposition Syrian National Council reported what it called a "massacre" of 230 civilians in Homs overnight Friday.
Reports said the Baba Amro neighborhood was the main target of today’s assault, while shells also landed in Al-Khalidiya, the main focus of Friday violence.
Meanwhile Russia and China have defended their double veto of a UN Security Council resolution on Syria, which called for President Bashar al Assad to stand down.
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Russia argued that Western powers had refused to reach a consensus, and said it would push for the rapid implementation of democratic reforms, AFP reported.
The Russian Foreign Minister, Sergei Lavrov, and Foreign Intelligence Service chief, Mikhail Fradkov, are due to visit Damascus on Tuesday.
Newspapers in China said the Western push for regime change did not adequately reflect the state of affairs in the country, the BBC reported.
The US Secretary of State Hillary Clinton has called the veto a "travesty" and vowed to push for new sanctions.
The French foreign minister Alain Juppé said Europe would also strengthen sanctions, and that France would help the Syrian opposition to organise itself.