Civil defence members search for survivors under the rubble at a site hit by an airstrike in west of Idlib city, Syria April 28, 2017.

Airstrikes struck a center of Syria’s rescuers known as the White Helmets in a rebel-held area in the country’s center, killing eight volunteers, opposition activists said Saturday.

The airstrike was one of the deadliest against the rescuers who operate in opposition-held areas and who have garnered world attention for operating in extreme conditions, pulling survivors out of recently struck areas. The volunteers have often been targeted by government airstrikes, in what are known as ‘double tap’ attacks, as they work to rescue others.

The local White Helmets in the central Hama province said an air raid on one of their centers in Kfar Zeita killed eight members of the team. The group said five bodies were lifted from the rubble and the rescuers continued to look for the others.

The Britain-based opposition monitoring group, the Syrian Observatory for Human Rights, said the number of those killed is likely to rise as the search mission continues.

It was not clear who carried out the airstrikes, as Syrian government and Russia aircraft have targeted opposition-held areas. The central Hama province have been scene to intense violence in recent weeks, as the government attempts to push back a rebel offensive.

Separately Saturday, Syria’s military said its troops and allied fighters repelled an attack by the ISIS group on a strategic area held by the government in southern Aleppo province.

The attack took place in Khanaser, southeast Aleppo – a strategic region that links Aleppo with central and western Syria. The area has changed hands many times during the conflict. But last year, government troops and allied fighters wrested control of Khanaser from ISIS.

The military media arm said ISIS attacked Um Mayyal village near a mountain range in Khanaser and other areas. The Observatory said ISIS fighters launched the attack on military posts in the area, triggering intense clashes and leaving many casualties.

ISIS-affiliated Aamaq news agency claimed ISIS fighters killed 30 government soldiers in the attack.

Near the capital, hundreds of Syrians from the rebel-held suburbs of eastern Ghouta near Damascus protested against infighting between the insurgent groups that began Friday and left dozens killed in the area.

The infighting came amid an intensified government offensive in the area near Damascus, which the rebels have controlled for years but has been increasingly squeezed by government advances.

“God rid us of all leaders,” the protesters chanted, criticizing the head of the insurgent groups for diverting their weapons from the front line with the government.

The infighting is pitting the powerful Army of Islam group against al-Rahman Corps and al-Qaida-linked group the Levant Liberation Committee, or Hayat Tahrir al-Sham. Each side blames the other for triggering the fighting in the power struggle over control of eastern Ghouta. Some activists have called on Army of Islam to rid eastern Ghouta of the powerful al-Qaida-linked group.

The Observatory said shots were fired at the protesters in one area, leaving five injured.

In 24 hours of fighting, the Observatory said at least 38 insurgents from the warring sides were killed. Damascus-based Shaam News Network put the number at 60, in addition to six civilians killed because of the clashes.

For the past three years, the government has been unable to regain control of the eastern suburbs of Damascus. But in recent weeks, an intensified offensive points to a new determination to retake the area.

On Saturday, activists reported a heavy air campaign against the area’s Qaboun neighborhood.

Civil defence members searching for survivors under the rubble, Syria April 28, 2017.