The attack came after soldiers who had abandoned the government forces burned a tank in the area, the rights group said.

Government forces killed two civilians during raids in the northern town of Jabal al-Zawiya, and another civilian was killed and five wounded in a dawn operation in southern Deraa province.

Powerful guns, some mounted on tanks, were used on people in Rastan, Talbisseh and Tir Maala, all in central Homs province, the Observatory added.

“At least 20 people were wounded, seven seriously, when soldiers using heavy machine guns on tanks began to open fire at sunrise in Rastan,” it said.

The Local Coordination Committees, which organize protests on the ground, reported a “massive deployment” of security forces in Rastan.

The protests are part of the wave of unrest across the Middle East and North Africa that unseated governments in Tunisia, Egypt and Libya. Assad’s crackdown has left more than 3,600 civilians dead, according to Ammar Qurabi of the National Organization for Human Rights in Syria. About 30,000 people have been detained and 13,000 are still being held, according to Qurabi.

The U.S. and European Union have imposed sanctions, including bans on oil exports, and called on Assad to cede power. They dropped efforts to impose United Nations sanctions in order to win votes for a Security Council resolution condemning the repression, a draft of which is due to be circulated on Wednesday. The government says its foreign enemies helped instigate the unrest.

In a blog he launched on Tuesday, British ambassador to Damascus Simon Collis said Assad’s regime saw “only one way out — the return to authoritarian rule where fear surpasses a desire for freedom.”

“This is a regime that remains determined to control every significant aspect of political life in Syria,” Collis wrote.

“It is used to power. And it will do anything to keep it.”

On Monday, Syrian Foreign Minister Walid Muallem, speaking at the annual U.N. General Assembly, accused foreign governments of trying to undermine the co-existence among Syria’s different religious groups.

Anti-regime protests had become a “pretext for foreign interventions,” he added.

Damascus does not accept the existence of popular opposition to the authorities, instead blaming “armed gangs” and “terrorists” for trying to sow chaos.

But U.S. State Department spokesman Mark Toner said: “I would say that the opposition’s shown extraordinary restraint in the face of the regime’s brutality and demanding their rights through peaceful unarmed demonstrations.”

“It goes without saying that the longer the regime continues to repress, kill and jail these peaceful activists, the more likely that this peaceful movement’s going to become violent.”

The opposition Syrian National Council meanwhile announced plans to meet in Istanbul this weekend to try to unify the fragmented coalition.

“We will meet on Oct. 1 and 2, in principle in Istanbul,” spokeswoman Bassma Kodmani told AFP. “Then we will talk about setting up committees.”

The council, which was set up in August, consists of 140 people. Half of them live in Syria and their names have not been made public for security reasons.

In New York, Chinese Foreign Minister Yang Jiechi urged the global community to “handle the Syrian issue in a prudent way so as to prevent further turbulence in Syria and its repercussions on regional peace.”

China has joined Russia in opposing sanctions against Syria.