Syrian rights groups say at least 34 people were killed Tuesday as government forces continued attacks on rebel strongholds and U.N. monitors reported an angry mob prevented them from reaching the embattled western town of al-Haffeh.

The Local Coordination Committees, an activist group with members throughout Syria, told VOA the casualties include 14 civilians dead in Deir al-Zour, 10 in Homs and eight in Aleppo. A number of government soldiers were among those killed.

Also Tuesday, news agencies quoted United Nations peacekeeping chief Herve Ladsous as saying he believes Syria is now in a full-scale civil war, with a “massive increase in the level of violence.”

But U.N. spokesman Martin Nesirky backed away from that characterization, telling reporters later “it is not for the U.N. to designate in that way.” Nesirky, however, did confirm “a qualitative shift and intensification” of the violence in Syria.

The U.N. mission in Syria said a crowd of what appeared to be local residents in al-Haffeh surrounded U.N. observers and threw rocks and metal bars at their vehicles, firing gunshots at them as they left the area. None of the observers were injured.

The United States has said it fears Syrian forces are planning to massacre civilians in the town.

LCC spokeswoman Rafif Jouejati said rebel fighters in al-Haffeh have been attempting to smuggle trapped civilians over the nearby Turkish border.

“We know there were some 30,000 residents trapped in the town of al-Haffeh and we also know members of the Free Syrian Army were trying to help residents flee the area and get transported to Turkey and that a small number of residents have been safely transported, but there are still thousands of residents trapped.”

Clashes in al-Haffeh began last week when security forces attempted to capture the strategic Sunni Muslim town, located close to the port city of Latakia and the Turkish border – and used by rebels as an active smuggling route for people and supplies.

Hundreds of rebels are facing a continued tank and helicopter-backed assault in al-Haffeh. The helicopter attacks – confirmed by the U.N. on Monday – are regarded as a significant escalation by government forces.

Jouejati told VOA that helicopter shelling and other aerial attacks by government forces have been occurring for months across Syria.

The spokesman for international envoy Kofi Annan said Tuesday that an international “contact group” will meet soon to discuss how to pressure Syria's government and opposition groups to implement the U.N.-Arab League envoy's tattered peace plan.

The contact group meeting has been in doubt because of Western opposition to Syrian ally Iran's involvement. The Iranian foreign ministry Tuesday welcomed a Russian proposal for Iran to be included despite strong reservations from the U.S., France and Britain.

On Monday, the United Nations accused Syrian security forces and pro-government “shabiha” militias of committing serious rights violations against children, including using them as human shields. The report also said children have been “victims of killing and maiming, arbitrary arrest, detention, torture and ill-treatment, including sexual violence.”

The U.S.-based Human Rights Watch said the U.N. Security Council should impose an arms embargo and other targeted sanctions on the Syrian leadership in response to the abuses described in the report. It said Syrian children are paying a “horrendous price” in the conflict.

The Britain-based Syrian Observatory for Human Rights said nationwide attacks by government and rebel forces killed at least 63 civilians and 21 troops on Monday.