Thousands of extra troops joined a "final push" to crush the Syrian uprising today.
Armoured divisions surrounded the besieged rebel fighters in Homs as the Red Cross urged a break in fighting to allow aid into the city, which has been under almost constant bombardment for three weeks.
But shells and heavy artillery again rained down on the Baba Amr district where the majority of the dissidents are dug in. Reports from the city said the field hospital has been hit, and video footage showed tanks moving through the city.
Rami Abdul-Rahman, head of the Syrian Observatory for Human Rights, said: "The human loss is going to be huge if they retake Baba Amr." He added that at least seven people had been killed today.
As the bloodshed escalated, there were signs that Russia and China's position was changing. They had vetoed UN Security Council resolutions backing Arab League plans aimed at ending the conflict but today Russia urged the UN to send a special envoy to Syria to help co-ordinate security issues.
Russia's UN ambassador Vitaly Churkin said help should be given after an agreement by Damascus to allow aid agencies to some cities, although Homs is excluded.
In Cairo, Arab League secretary-general Nabil Elaraby said: "There are some indications, especially from China and to some degree from Russia, that there may be a change in their stance."
