Seven members of the White Helmets rescue group have been reportedly shot dead by unidentified gunmen on Saturday, August 12, 2017 in Syria.
It was active in rebel-held eastern Aleppo before the territory was seized by forces loyal to President Bashar al Assad.
The White Helmets said in a statement: "The civil defence centre in Sarmin was the target of an armed attack by unknown assailants in which seven volunteers were killed".
The group and opposition activists also revealed that the attackers also stole two vans, helmets and walkie-talkies.
It was not immediately clear whether the motives for the raid were political or purely criminal.
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"Colleagues came in the morning for the change of shift and found them dead", its director, Rami Abdel Rahman, said.
The SCD receives millions of pounds worth of funding from many Western government including the United Kingdom and the US.
The White Helmets emerged in 2013, working to rescue civilians in rebel-held areas.
Their detractors, including President Bashar al Assad's regime and his ally Russian Federation, accuse them of being tools of their global donors.
In this photo provided by the Syrian Civil Defense group known as the White Helmets, Syrian Civil Defense workers search through the rubble after airstrikes in the village of Hass in the Idlib province, Syria, Oct. 26, 2016.