BEIRUT (Reuters) - Members of Syria’s Druze minority have helped repel a rebel attack on an army base in the south, mobilizing to confront insurgents including al Qaeda’s Nusra Front who are trying to build on gains against President Bashar al-Assad.

The Syrian Observatory for Human Rights, a UK-based organization that tracks the war, said on Friday rebels had been driven from the base, which they had partly captured on Thursday, by air strikes and Druze fighters from nearby Sweida.

A Druze leader from Sweida said young men from the city had helped recapture the disused al-Thala airbase. A rebel leader confirmed that the government side had sent reinforcements to the base.

Spread between Syria, Lebanon, Israel and Jordan, the Druze are viewed as heretics by al Qaeda and Islamic State because of their religion, an offshoot of Islam incorporating elements of other faiths.

They have moved into the spotlight of the Syrian war this week, with advances by insurgents triggering statements of concern about their fate from both Israel’s president and Druze figures in Lebanon.

Some Druze leaders have warned of an existential threat facing their kin after Nusra Front fighters shot dead 20 people in a Druze village in northwestern Syria on Wednesday - an incident ignited by Nusra’s attempt to confiscate a house.

Groups fighting to topple Assad say he is trying to exploit sectarian fear to shore up his support base. Bashar al-Zoubi, the head of a rebel group involved in the battle for the army base, said those attempts would fail, adding that the Druze know the “regime is collapsing and cannot protect them”.

“REBEL RETREAT”

Insurgents battling Assad in southern Syria include the Nusra Front but also groups that do not share its jihadist ideology and are trying to calm Druze fears.

Insurgent groups have been advancing toward Sweida from the west and the east, where Islamic State has been mounting attacks on army positions.

The Druze role was key in repelling the attack on the base, said Rami Abdulrahman, who runs the Observatory that monitors the four-year-old civil war in Syria.

“If they hadn’t mobilized, (the insurgents) wouldn’t have been repelled,” he said. “There is a rebel retreat.”

The Druze leader, Sheikh Abu Khaled Shaaban, said young men from Sweida had deployed in several areas including the airport under the umbrella of the National Defense Force and “popular committees” that are battling alongside the Syrian army. State TV said dozens of Sweida residents had joined the army and NDF.

“Matters are heading towards calm and complete control of the situation,” Shaaban told Reuters by telephone from Syria.

Zoubi, the rebel leader, said the base remained in government hands on Friday. But he added that there was “coordination between us and the sheikhs of Sweida” - a reference to community elders whom he did not identify.

Echoing comments from other, secular-leaning opposition groups in recent days, he said the Druze would be treated as Syrians with the same rights as other citizens.

Since March, an array of insurgent groups have gained ground from Assad in the northwest, the east and the south.

The southern rebels, operating in a region just 100 km (60 miles) from Damascus, seized a major army base on Tuesday in Deraa province, building on victories including the capture of the Nasib border crossing with Jordan.

Druze in Israel have been lobbying for arms to be sent to Syria, a U.S. official has said. Lebanese Druze politicians aligned with the Syrian government have also called for the arming of their kin in Syria.

But Walid Jumblatt, a Lebanese Druze leader who backs the uprising against Assad, has urged the Druze of Sweida to reconcile their differences with the Syrian opposition.

He convened a meeting of Druze spiritual figures in Beirut on Friday, declaring afterwards that the shooting in northwestern Syria was a isolated incident.