Clinton condemns latest violence in Syria

US Secretary of State Hillary Rodham Clinton says Syria's recent violence is "simply unconscionable" and is blaming President Bashar Assad for "doubling down" on his harsh crackdown.

Referring to reports of a new massacre in central Hama province, she says Syria cannot be a peaceful, stable and democratic country until Assad leaves power.

Speaking in Turkey, Clinton says she and more than a dozen top foreign officials she has met have agreed on a set of principles for a new Syria.

They include the need for Assad to leave power and depart Syria — explicitly calling for Assad's exile.

Syrian opposition groups say scores died in new violence on the outskirts of Hama. One organization claims pro-government militiamen killed at least 78. Syria rejects the claims as "absolutely baseless."

The exact death toll and circumstances of the overnight killings in Mazraat al-Qubair on the outskirts of Hama were impossible to confirm but the violence is bound to reinforce the growing belief that a peace plan brokered by international envoy Kofi Annan is unraveling as the country spirals toward civil war.

The violence comes on the heels of a horrific massacre in late May in Houla, a cluster of villages in the central Homs province, which left over 100 dead including many children and women gunned down in their homes. UN investigators blamed pro-government gunmen for at least some of the killings but the Syrian regime denied responsibility and blamed rebels for the deaths. The Houla massacre triggered international outrage and a coordinated expulsion of Syrian diplomats from world capitals.

Syria on Thursday said "an armed terrorist group committed an appalling crime" in Mazraat al-Qubair, killing nine women and children. A government statement published on the state-run news agency SANA said that after the crime, residents there appealed on Syrian authorities in Hama to intervene to protect them, adding that competent authorities headed to the farm and stormed a hideout of the group and clashed with them.

Clashes resulted in the killing of all members of the group. Two security agents were killed and five others wounded, it said.

The statement said the killings were meant to put pressure on the Syrian regime ahead of the UN Security Council meeting.

British Prime Minister David Cameron urged concerted action from the international community against Syrian President Bashar Assad's regime following the latest reports. He said Thursday that if the reports of the "brutal and sickening attack" are true, it adds further proof that the Assad regime is "completely illegitimate and cannot stand."

Speaking during a visit to Norway, Cameron insisted more must be done to isolate Assad's regime and show that "the whole world" wants to see political transition in Syria and condemns "absolutely" the Syrian regime.