QUSAYR, Syria -- After more than six months of fighting, Syria’s largest rebel group appears to have developed into a resilient guerrilla force, unable perhaps to hold large swaths of territory for very long but still capable of inflicting heavy casualties on the Syrian military and operating fluidly within supportive populations.

The story of the Katiba Farouq, or the Farouq Brigade, has been eclipsed over the past year by news coverage that’s remained focused on the Syrian government’s shelling of urban neighborhoods. But in the months since they took up arms in August, Farouq fighters have discovered the Syrian military’s weaknesses, and despite some reversals, still appear capable of inflicting heavy casualties whenever the Syrian army attempts to enter rebel-held areas.

The rebels plan only to gain strength. “Now we are reorganizing ourselves and creating a military council,” said Mohamed Idris, who was the leader of Farouq’s branch in Baba Amr, the Homs neighborhood that was heavily damaged by Syrian rockets and heavy artillery before the rebels there finally withdrew at the end of February as they ran short of ammunition.

Idris said he and Farouq’s overall commander, Abdel Rizaq Tlass, were wounded in the Homs shelling and escaped together by swimming the Orontes River. Tlass stayed in Homs, while Idris moved south with his men to this all but abandoned city that once was home to 35,000 people near the border with Lebanon.

Tlass appeared in a short video posted on YouTube by Syrian anti-government activists on Sunday, offering to protect U.N. observers if they would stay in rebel-held areas of Homs.

There are many rebel factions fighting against the government of Syrian President Bashar Assad, but Farouq now is considered the largest of the groups claiming to fight under the banner of the Free Syrian Army, the name adopted by the loosely organized army of defectors and volunteers who make up the armed wing of the anti-Assad uprising.

What the Farouq fighters have found is that the Syrian army, as a force built for a potential conflict with Israel, is poorly equipped for the type of asymmetrical combat the guerillas engage in. That allows the guerillas to inflict heavy casualties on the military when the two sides engage in close combat. It is one reason the Syrian military prefers launching artillery attacks on rebel-held cities from long distances.

The rebels also have suffered heavy losses. Idris said he had 250 soldiers under his command during the fighting in Baba Amr, and that 114 of those had been killed in the fighting. Many of those survivors decamped with him to Qusayr, where they battled the Syrian military last week, repelling incursions by the military into the rebel-held portion of Qusayr on consecutive days.

Idris, limping, stayed clear of the front line at the request of his underlings. He directed the fighting from a house-turned-bunker in northern Qusayr.

“If the international community really wants peace in Syria, they will help us with weapons,” Idris said, making it clear the group was planning to step up attacks against the Syrian military. He said his fighters would continue to plant roadside bombs to destroy military vehicles outside of populated areas.

“We will attack the Syrian army in their bases and their checkpoints and try to capture their weapons,” he said. “We are also training fighters. We have many new volunteers without military experience.”