Gunmen kill five White Helmet rescue workers in Aleppo province

Armed men stormed the al-Hader centre before dawn and fired on the first responders inside. 

Four volunteers died on the spot and a fifth died later in hospital. 

Founded in 2013, the White Helmets are a network of first responders who rescue the wounded in the aftermath of airstrikes, shelling or blasts in rebel-held territory. They have saved thousands of people, digging civilians out of bombed out homes.

The al-Hader centre is located in an area of Aleppo controlled by Tahrir al-Sham (HTS), which was once al-Qaeda's affiliate in the war-torn country. 

"At around 2:00 am, an armed group stormed the al-Hader centre, blindfolded the staff members who were on the night shift, and killed five of them," said Ahmad al-Hamish, who heads the centre.

"Two others were wounded and another two were able to flee. The attackers were masked and escaped after stealing some equipment and generators," he said. 

It was unclear whether the attack was politically motivated or a robbery-gone-wrong. 

More than 200 White Helmets rescuers have been killed in Syria's seven-year war, usually in bombing raids or shelling on their centres.

In August, seven White Helmets members were killed in a similar attack in the town of Sarmin, in neighbouring Idlib province. 

Most of Idlib is held by HTS, as well as a part of Aleppo and the adjacent province of Hama. 

Tensions are on the rise there, with a wave of intra-opposition assassinations and clashes leaving at least 20 rebels dead in 48 hours, according to the Syrian Observatory for Human Rights. 

"You cannot separate the al-Hader incident from the assassinations and other killings that have been happening more and more in recent weeks in areas under HTS control," said Observatory head Rami Abdel Rahman.

The population of Idlib has grown exponentially after evacuation agreements were reached between rebel groups and the Syrian regime in former opposition held areas. 

The killings also come as the White Helmets are facing budget constraints after the US froze funding to the group earlier this month. 

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