It looks like a sandstorm has blown in, the air thick with dust as a white van screeches to a halt and volunteers from Syria's ‘White Helmets' dash in to help dazed survivors after an air strike in Aleppo. In life before the war these volunteers of the Syrian Civil Defense, also known as the White Helmets, were ordinary citizens, from bakers to teachers to painters. They are now on the frontline of the conflict and the first in when the shells hit. "We used to be called to an attack once a month that had 30 martyrs, but during the Russian intervention we were called to many attacks, where the numbers of martyrs was more than 100 and the injured more than 200," said Raed Al-Saleh, director of the White Helmets. Saleh used to be an electrical supplies salesman before heading up the search and rescue operation of the group of unarmed men and women that was set up to fill the void of emergency responders no longer on hand when the bombs dropped. The non-sectarian group was officially formed in 2014 and now has 3,000 volunteers, describing itself as the largest civil society organisation operating in areas outside of government control, and many more wish to join. "The strikes have targeted vital centres that provide help to people on a regular basis and then attacking the people that rush to help. Recently, 10 hospitals were destroyed," Saleh said in an interview during a recent visit to London. UNDISCLOSED LOCATIONS Many of the volunteers train across the border in Turkey before deploying to one of the 114 centers dotted across Syria, including in the besieged areas, the exact location of which remain undisclosed as they have received death threats. They receive their funding from members of the International Syria Support Group (ISSG), led by a group of countries including the United States and Britain. They say they are neutral, impartial and wanting to help anyone, no matter what side they are on — but their work has come at a cost, with at least 92 White Helmets volunteers killed while saving others. With huge parts of Syria flattened, rescue workers say part of the challenge lies in finding a hospital for the wounded. The medical charity Medecins Sans Frontieres (Doctors Without Borders) has strongly criticized Syria's warring sides for attacking clinics and hospital staff. The United Nations estimates almost half a million Syrians are living under siege, and more than 11 million from a population of 23 million have been forced from their homes during the conflict with more than 250,000 killed. "Sometimes when we are taking someone to the nearest hospital we don't find spaces so we need to go further to the next one," Saleh said. "Sometimes they don't make it .. The pain we feel is massive while rescuing people, while looking for a hospital, as most of the hospitals in the city have been completely destroyed." As the Syrian conflict enters its sixth year the team said they have also reached their own tragic milestone having rescued over 50,000 of their own countrymen. — Thomson Reuters Foundation