Gunbattles between pro- and anti-Syrian groups in northern Lebanon killed at least seven people and wounded 22 on Saturday, security officials said, as activists reported fresh shelling in a region in central Syria where a massacre last week left more than 100 people dead.

The clashes were the latest to hit the Lebanese port of Tripoli. Repeated outbreaks of violence in the city, the country's second largest, are seen as a spillover from Syria's conflict and has raised fears of an escalation in sectarian tensions in Lebanon.

The fighting in Tripoli started shortly before midnight Friday and intensified Saturday, the officials said on condition of anonymity in line with regulations.

Lebanon and Syria share a complex web of political and sectarian ties and rivalries, which are easily enflamed. Clashes in Tripoli last month killed at least eight people.

The conflict pits Sunni Muslims who support Syrian rebels trying to oust President Bashar Assad against members of the Alawite sect, an offshoot of Shiite Islam of which Assad is a member.

Smoke was seen billowing from several apartments near the city's Syria street, the split between the mainly Sunni Bab Tabbaneh neighborhood and the adjacent, Alawite-majority Jabal Mohsen, on a hill overlooking its rival. The area around Syria street was mostly empty and gunmen were seen roaming the streets.

"We are being targeted because we support the Syrian people," a Sunni gunman told Associated Press Television. "We are with you (Syrian people) and will not abandon you."

In Syria, activists said government troops fired shells at Houla, a cluster of farming villages in the central province of Homs where the U.N. says at least 108 people -- including 49 children under the age of ten -- were killed on May 25.

The opposition and the government have exchanged accusations over the massacre with each side blaming the other.

Syria has come under deep international isolation since its forces launched a ferocious crackdown on dissent nearly 15 months ago, but the Houla massacre has brought a new urgency in calls to end the crisis.

In Qatar, the head of Syria's largest exile opposition group said Saturday he would welcome Arab military action aimed at ending attacks by Assad's regime against Syrian rebel forces and civilians.

Burhan Ghalioun, the leader of the Syrian National Council, made the comments before a meeting of Arab League foreign ministers. The envoys are to discuss the bloodshed in Syria, including the Houla massacre.

Gulf nations such as Saudi Arabia and Qatar have pledged funds to aid Syria's rebels, but there is no direct evidence that the money is reaching anti-Assad forces or that the rebels are becoming better armed. The Arab League, however, does not appear ready to deploy its own troops. Kofi Annan, the international envoy for Syria, is also in Doha.

As a way to curb the violence in Syria, Arab League chief Nabil Elaraby suggested that the U.N.'s nearly 300-strong observer mission be changed into a peacekeeping role.

"What is needed today is not only observing and investigating but supervising that the violence stops," Elaraby told the meeting. "One of the alternatives could be amending the authorization regarding the observers so that they become a peacekeeping force."

The deployment of unarmed U.N. observers is part of Annan's six-point peace plan, which includes a cease-fire that is to lead to talks between the regime and its opponents. The cease-fire, however, has never really taken hold, although world leaders continue to pin their hopes on it because there is little appetite in the West for a Libya-style intervention.

Annan warned Arab officials that "the specter of all-out civil war, with a worrying sectarian dimension, grows by the day," in Syria, and added that the crisis is spilling over to neighboring countries, an apparent reference to Lebanon.

"The six-point plan is not being implemented, as it must be," Annan said. "The situation is complex, and it takes everyone involved in the crisis to act responsibly if the violence is to stop. But the first responsibility lies with the Syrian Government, and with President Assad."

He called on Assad to implement the plan and "make bold and visible steps immediately."

On Friday night, state TV aired interviews with two witnesses from Houla who said the victims of the massacres were members of families that support the government and did not take part in anti-Assad protests. The witnesses names and faces were not made public for their own safety, according to the station.

Those statements contradicted accounts of witnesses who blamed "shabiha" or the shadowy gunmen who operate on behalf of Assad's regime. The U.N. also said it had strong suspicions those pro-regime gunmen were responsible for much of the bloodshed in Houla.

In Brussels, U.N. High Commissioner for Human Rights Navi Pillay said Saturday there should be no amnesty for crimes committed in Syria, even if potential prosecution might motivate members of the regime to cling to power at all costs.

She said international leaders may be drawn to "politically expedient solutions which may involve amnesty or undertakings not to prosecute," but she insisted there cannot be amnesty for very serious crimes.

Pillay spoke a day after the Human Rights Council voted overwhelmingly to condemn Syria over the slaughter in Houla.Since the massacre occurred, activists have reported that government troops have shelled the area almost daily. They say many residents have the area for fear of a new massacre.

The Britain-based Syrian Observatory for Human Rights said the shelling concentrated on the village of Tal Dahab in Houla.

The Observatory and the Local Coordination Committees also reported shelling and clashes between troops and rebels in the central city of Homs, the southern province of Daraa and some suburbs of the capital Damascus.

Activists say as many as 13,000 people have died in Assad's crackdown against the anti-government uprising, which began in March 2011 amid the Arab Spring. One year after the revolt began, the U.N. put the toll at 9,000, but many hundreds more have died since.