TRIPOLI, Lebanon: The sheikh, a small wiry figure with long straggly hair and an intense gaze, leaned forward proffering his cellphone.“Look, look,” he said. “This is what the Shabiha are doing to us.”

The flickering video images on the phone showed two prisoners lying on the side of a road with their hands tied behind their back. A man holding a knife bends down and pulls back the head of the first prisoner and with a few savage thrusts severs it from the body. The executioner then repeats the act with the second prisoner. The final image shows the severed heads placed on top of the bodies.

Another video shows a similar sickening scene. This second executioner is dressed in black with a black ski mask covering his face. He picks up the freshly severed head, drops it on the road and gives it a kick like a football to the laughter of his off-camera companions.

It was impossible to confirm the identity of the killers and the prisoners, although there were no Islamic exhortations – such as “Allah u-Akbar” – that usually accompany such executions when carried out by Islamist extremists.

But how did the sheikh obtain the video if it was shot by an Alawite Shabiha militiaman?

“When we capture the Shabiha, we always check their cellphones for information and sometimes we find these videos on them,” said Sheikh Zuheir Amr Abassi, from Deraa in southern Syria and spokesman of the Islamic Supreme Council of Syria.

Abassi, who said he helps provide logistical support for the rebel Free Syrian Army, was among a group of five FSA officers and soldiers in hiding in the sheikh’s small drab apartment in the Bab al-Tabbaneh neighborhood of Tripoli.

Sunni-populated areas of north Lebanon, particularly Wadi Khaled, are fast becoming relative safe havens for growing numbers of FSA fighters to regroup and plan attacks against the regular Syrian army and security forces.

“The only place we feel really safe is here in Bab al-Tabbaneh,” Abassi said.

The FSA men were from Homs and they regularly slip across the border using secret smuggling trails. But they denied that they launched military operations from Lebanese territory.

“We are respecting Lebanese sovereignty and Lebanese law and we don’t launch attacks from here. But we are operating very close to the border on the Syrian side,” said Mohammad, one of the officers from Homs in his late 30s who wore a thick wool jacket against the cold.

The FSA is composed of deserters from the regular Syrian army augmented by civilian volunteers, and is commanded by Colonel Riad al-Assad who defected last summer and lives in a refugee camp in Turkey. Its strength is unknown although FSA leaders and Syrian opposition figures have claimed numbers as high as 40,000. Others say the figure is much lower. “We’re deserting because the regime makes us kill civilians. The Alawite officers stand behind us and they shoot anyone they see not firing at protesters,” said Ahmad, who said he deserted six months ago from a military intelligence unit in Damascus.

Lately, the FSA has escalated its attacks, managing to carve out tenuous regime-free pockets of territory, even on the outskirts of Damascus. At least 16 Syrian soldiers were killed Sunday in two separate attacks, one in the Jabal al-Ziwiya in the northwest and the other near the Damascus suburb of Sahnaya.

As efforts to find a diplomatic solution to the 10-month uprising look doubtful, international attention is focusing more closely on the FSA and whether it could play a decisive role in toppling the Assad regime in the months ahead.

Abassi said that there are secret channels of communication between the FSA and soldiers and officers serving in the regular army.

“A potential deserter will contact us and give us his name and rank. We will ask him his job in the army. If he’s of use to us, we tell him to stay where he is so he can smuggle weapons to us or provide us with intelligence. Otherwise, we tell him to desert only when he has a rifle and plenty of ammunition,” he said.

As an example, Abassi recounted how an army officer in charge of a weapons depot was recruited into the FSA. He says the officer was given a Thuraya mobile satellite phone and asked to make arrangements for the FSA to raid the arms depot.

“He called us one night and said all was clear. We sent 20 guys with duffle bags to the depot and they filled them with weapons and ammunition,” he said.

The FSA has a cellular structure with units operating from towns and cities across the country. Abassi says there is no direct communications between the battalions, but each unit commander is contact with Colonel Assad in Turkey.

The FSA also includes religious cadres. While FSA units are granted autonomy to attack targets of opportunity without prior authorization, Abassi said, for pre-planned attacks the more devout cadres seek a fatwa, a religious edict, from Syrian dissident clerics.

“It’s up to each unit whether they want a fatwa before any military operation. We usually obtain fatwas for each attack we plan, but for those that don’t, if they kill someone, it’s between them and God when they die,” Abassi says.

The FSA concentrates its attacks on interrogation centers, arms depots and against pro-regime Shabiha militiamen, who have earned a reputation among the opposition for their brutality. There is evidence that some units have managed to obtain relatively advanced systems such as RPG-29 and Kornet-E anti-tank missiles both of which can easily penetrate the armor of Syrian BMP fighting vehicles used by frontline troops. But the FSA generally suffers from an unreliable supply of weapons and ammunition.

“We need everything,” said Mohammad. “RPGs, PKC [light machine guns], silencers, ammunition. There are so many of us that we need much more than we are getting.”

The FSA has called for international assistance in establishing no-fly zones and safe havens where the regular Syrian forces cannot operate. However, there is little appetite in the West to intervene militarily in Syria, even to the extent of establishing safe havens. “If we were given these two, most of the army would desert and join us,” Abassi said. “We are not asking the West to intervene but just to give us weapons, safe havens and no-fly zones. We can do the rest.”