Several youth from al-Mankoubeen area in the northern city of Tripoli erected on Saturday tents near al-Nour mosque to protest media reports saying that a group of Lebanese Islamists from the city were killed in the Syrian border town of Tall Kalakh.

The National News Agency reported that the youth are demanding authorities to determine the fate of the Twenty-two men.

Syrian Internet and mobile phone links remained cut for a third straight day on Saturday, an AFP correspondent in Damascus reported, amid U.S. accusations the government is deliberately seeking to deprive the opposition of communications.

But activists and human rights monitors said that ordinary civilians were harder hit by the blackout than the opposition as they unable to use cellphones even to call for emergency assistance in the event of casualties from the persistent violence rocking the country.

The army shelled the southwestern outskirts of Damascus on Saturday as it mounted an offensive against rebel fighters holed up in the area, the Syrian Observatory for Human Rights said.

"The army shelled orchards that extend from Kfar Sousa to Daraya and are taking on rebels who control the region," said the Britain-based watchdog, which relies on a network of activists and medics on the ground.

U.N. leader Ban Ki-moon predicted Friday that Syrian refugee numbers will surge to more than 700,000 by January as the country's conflict reaches "appalling heights of brutality."

U.N.-Arab League envoy Lakhdar Brahimi warned alongside Ban that Syria is now in danger of becoming a "failed state" as he appealed for new international efforts to reach a political settlement.

Russia said Friday it was willing to "set aside differences" with Turkey ahead of talks between Russian President Vladimir Putin and Turkish officials that will focus on Syria.

"Turkey and Russia have clearly different positions on several questions, notably the Middle East, but these must be put aside when Mr. Putin holds talks in Istanbul," Russian Ambassador Vladimir Ivanovsky told reporters.

Fighting raged around Damascus on Friday as Internet and phone links in Syria remained cut for a second day and rebels consolidated gains in the east, capturing an oil field near the Iraqi border.

The Syrian Observatory for Human Rights said the road from the capital to Damascus airport had reopened, a day after fighting during which a bus carrying airport employees was hit by a shell, killing two people.

Google and Twitter announced Friday they have reactivated a voice-tweet program to allow Syrians affected by the shutdown of the Internet to get messages out.

The service allows people with a telephone connection to compose and send a tweet by speaking on their phones.

At least 17 Lebanese Islamists were killed in Syria on Friday as they were infiltrating the country, reported various media outlets.

Agence France Presse said that 17 Lebanese Sunni fighters were killed in Syria's Tal Kalakh border area in an ambush carried out by regime forces.

Dutch police have arrested three alleged would-be jihadists who were about to leave The Netherlands to go and fight alongside rebels in Syria, the national Prosecutor's Office said Friday.

"Detectives arrested three men on Thursday who apparently planned to travel to Syria to participate in a violent international jihad," it said in a statement.

Demonstrators booed the rebel Free Syrian Army on Friday in regions where Islamist fighters have a strong presence, in videos posted on the Internet by activists.

"Free Army, go to the front lines," protesters in Aleppo's eastern district of Shaar shouted, criticizing FSA fighters who stay behind in rebel strongholds.