The death toll in Syria's civil war has passed 45,000, a watchdog said Wednesday, as peace envoy Lakhdar Brahimi looked to Russia for help in his faltering bid to find a negotiated settlement.
Washington meanwhile gave a cautious welcome to reports that Syria's army police chief had defected to the opposition.
"In all we have documented the deaths of 45,048 people," Rami Abdel Rahman, director of the Syrian Observatory for Human Rights, told AFP. More than 1,000 people had been killed in the past week alone, he added.
The Observatory relies on a network of medics and activists on the ground. It said the real number of those killed since an uprising against President Bashar al-Assad erupted in March 2011 could run as high as 100,000, with both sides concealing many of their casualties.
The grim statistics added gravity to a UN warning that the humanitarian situation is rapidly deteriorating.
The UN High Commissioner for Refugees "estimates that if fighting in Syria continues, the refugee figure could reach 1.1 million by June 2013," a report said. That is double the current number of those registered by the United Nations.
In the past 24 hours, more than 1,000 Syrians crossed into Turkey, a Turkish foreign ministry official said Wednesday, three days after a deadly regime air strike on a bakery in the central Hama province.
Brahimi arrived in Syria on Sunday to push a new initiative aimed at ending the bloodshed and getting the regime and opposition to the negotiating table.
A UN Security Council diplomat, however, said the veteran Algerian diplomat had received no support from any of the warring parties.
"Assad appears to have stonewalled Brahimi again, the UN Security Council is not even close to showing the envoy the kind of support he needs and the rebels will not now compromise," the diplomat said on condition of anonymity.
Opposition activists also attacked Brahimi.
"Brahimi's arrival in Damascus to discuss a new political initiative to solve the crisis caused by the regime... has not put a stop... to massacres," said the Local Coordination Committees, a grassroots network of anti-regime activists.
Brahimi is to hold talks on Saturday with Damascus ally Moscow, Russia's Deputy Foreign Minister Mikhail Bogdanov told the ITAR-TASS news agency.
Russia's foreign ministry said Brahimi himself had requested the meeting.
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-- US gives cautious welcome to defection --
Foreign Minister Sergei Lavrov said Moscow was pushing Brahimi to ensure that the warring sides commit to a June peace plan that calls for a transition of power without making an explicit demand on Assad to step down.
Syria's deputy foreign minister, Faisal Muqdad, was already in Moscow for talks on Wednesday.
In a new setback for Assad, Syria's military police commander General Abdel Aziz Jassem al-Shallal announced his defection in a video posted online Wednesday.
The army had "deviated" from its mission of protecting Syria, he said, accusing them of having turned into "murderous gangs".
The US State Department gave a cautious welcome to the news, while stressing they were not able to confirm it.
"If true, this would be yet another sign of the regime crumbling from within, as those around Assad realize that the end of his rule is inevitable," acting spokesman Patrick Ventrell said.
"We continue to encourage regime officials and forces to reject the horrific actions of the Assad regime," he added.
"Syrian officials should stand with the Syrian people."
Women and children were among at least 20 people killed in tank shelling of a farming village in the northern province of Raqa, said the Observatory, putting the day's death toll across Syria at 118.
"At least 20 people, among them eight children and three women, were killed in shelling by regime forces of farmlands in Kahtaniyeh village, west of the city of Raqa," it said.
Amateur video posted online by activists showed several bloodied bodies, including at least one of a child, laid out on blankets in a house.
State television blamed "terrorists" -- a reference to rebels battling the regime -- for the attack.
The Observatory also reported fresh clashes in the Palestinian refugee camp of Yarmuk in southern Damascus, the scene of fierce fighting last week; and near Wadi Deif base in the northern province of Idlib, where it said 20 rebels had been killed.