The death toll in Syria's bloody crackdown on opponents of President Bashar al-Assad in the city of Hama and elsewhere climbed on Tuesday and Russia said it would not oppose a U.N. resolution to condemn the violence.

Russia, an old ally of Syria, had long resisted any such measure by the U.N. Security Council, where it holds a veto. The Foreign Ministry in Moscow cautioned that any resolution should refrain from sanctions and other unspecified "pressures."

Three more civilians were killed in Hama, including two brothers, Khaled and Fateh Kanil, who died when pro-Assad "shabbiha" militiamen fired at their food-laden car, two residents, one of them a doctor, told Reuters by telephone.

They said a brief riot appeared to have broken out late on Monday at Hama's main prison. Two shabbiha militia buses were seen heading there at night and smoke rose from the compound as the militiamen shouted "God, Syria, Bashar, only" from inside.

"There is damage to the northern section of the jail and some say burnt bodies of prisoners were taken out of the complex," one of the residents said.

Tanks pounded residential neighbourhoods across Hama, the scene of a 1982 massacre, after evening prayers on Monday, the first day of Ramadan, the Muslim fasting month, witnesses said.

State news agency SANA said "hundreds of masked gunmen on motorbikes" had set fire to the main law court in Hama on Monday afternoon and had also vandalised much of the building.

Human rights campaigners said assaults by Assad's forces across Syria on Monday and Tuesday had killed at least 27 civilians, including 13 in Hama, where troops and tanks began a violent operation to regain control on Sunday.

That brought the total to about 137 dead throughout Syria in the past three days, 93 of them in Hama, according to witnesses, residents and rights campaigners.

Syria's state news agency said "armed terrorist groups" had killed eight policemen in Hama. The government blames such groups for most killings in the five-month-old revolt, saying more than 500 soldiers and security personnel have died.

The plight of Hama has prompted many Syrians to stage solidarity marches since the start of Ramadan. But Assad's tough response suggests he will resist calls for democratic change that have swept Syria and much of the Arab world this year.

Syria has incurred international opprobrium for its harsh measures, but need not fear the kind of foreign military intervention that NATO launched to support rebels in Libya.

The top U.S. military officer called for a swift end to violence in Syria, but only diplomatic pressure was in view.

"There's no indication whatsoever that...we would get involved directly with respect to this," Admiral Mike Mullen, chairman of the Joint Chiefs of Staff, said in Baghdad.

NO AGREEMENT

Consultations at the Security Council on Monday failed to produce agreement on adopting a Western-backed draft resolution condemning Syria or settling for a less binding statement.

The Russian Foreign Ministry's Middle East and North Africa Department Chief, Sergei Vershinin, said his country was not "categorically" against adopting a U.N. resolution on Syria.

"If there are some unbalanced items, sanctions, pressure, I think that kind of pressure is bad because we want less bloodshed and more democracy," he added.

Syrian Deputy Foreign Minister Faisal Mekdad urged India to ignore Western "propaganda" during its month-long presidency of the Security Council, which began on Monday.

"What we expect India to do is not to allow Western countries to use the U.N. as a forum to support terrorism, to support extremism and to support the killings of innocent people," Mekdad told India's CNN-IBN television channel.

The U.N. High Commissioner for Human Rights warned Syrian authorities that the world was watching the violence and said those who had violated human rights must be brought to account.

"There is a need for an international, transparent, independent and prompt investigation into the violence, the killings, the excessive use of force, the arbitrary arrests, ill-treatment and torture that the people of Syria have been subjected to," Navi Pillay said in a statement.

Italy recalled its ambassador from Syria in protest at the "horrible repression of the civilian population" and urged other European Union members to do the same.

The EU formally added five more Syrian officials to an existing list of 29 individuals headed by Assad, whom the 27-nation bloc has targeted with asset freezes and travel bans.

"Today further EU targeted sanctions on Syria come into force. The message is clear and unambiguous: those responsible for the repression will be singled out and held accountable," British Foreign Secretary William Hague said.

Apart from the 13 deaths in the latest Hama violence, two civilians were killed in the town of Albu Kamal on the Iraqi border, three in the city of Homs, two in the port city of Latakia and six in the Damascus suburb of Erbin after protests following night-time Ramadan prayers, rights activists said.

STARK MEMORIES

The attack on Hama has evoked memories of a bloody 1982 confrontation when Assad's father Hafez al-Assad put down an armed Islamist revolt, killing many thousands of people.

"The shells are falling once every 10 seconds," a witness in Hama told Reuters by telephone on Monday. The thump of artillery and explosions could be heard in the background.

YouTube footage, purportedly from Hama, showed tanks and smoke, with the sound of explosions and shouts of "Allahu Akbar (God is great)...We are witnessing the reforms of Bashar."

Another video shows a man lying on a street with his head sliced off by shrapnel.

With most foreign reporters barred from Syria, it was impossible to verify the content of the clips.

Nor was it possible to verify footage shown on Syrian state television, also said to be from Hama, which showed gunmen firing at the military from streets and rooftops. It also shows scenes of dead soldiers being thrown into a river.

Security forces, dominated by Assad's minority Alawite sect, had besieged restive Hama, a mainly Sunni Muslim city of 700,000, for nearly a month before the assault.