Syrian rights groups say security forces killed five more people across the country Thursday, as tensions escalate in an eight-month government crackdown on protesters.

News of the deaths in Deir Ezzor, Homs, and Idlib, came Thursday from the Britain-based Syrian Observatory for Human Rights. There was no independent confirmation of the casualties.

Meanwhile, international pressure continues to mount against Syrian President Bashar al-Assad and the killing of protesters.

European Union foreign policy chief Catherine Ashton and Mr. Assad's uncle, an exiled former Syrian military commander, both called Thursday for the Syrian leader to leave power.

At the United Nations, Germany, Britain and France continued to push for a resolution condemning the bloody crackdown on anti-government protesters.

China and Russia vetoed a similar U.N. Security Council draft resolution last month, and expressed renewed concern Thursday. Chinese Foreign Ministry spokesman Liu Weimin called for the crisis to be resolved through political means. And Russian Foreign Minister Sergei Lavrov urged all sides to resolve their differences peacefully. He said an attack on a Syrian military base by the Free Syrian Army was “very much like a civil war.”

The Free Syrian Army is made up of defectors from government security forces.

French Foreign Minister Alain Juppe also rejected the use of force in Syria Thursday but told French radio Syrian opposition groups must get more organized. Juppe said France is trying to help the Paris-based Syrian National Council.

These latest developments follow an ultimatum from Arab League ministers on Wednesday giving Syria's government three days to end the bloodshed and allow in teams of observers to monitor compliance. They did not say what will happen if Damascus fails to comply.

Earlier in the week, the league also voted to suspend Syria's membership.

Syria is only the third nation in the Arab League's history to be suspended.

The United Nations says at least 3,500 people have been killed in connection with the Syrian revolt since March. Syria blames much of the violence on foreign-backed terrorists and religious extremists.