In Aleppo, Syria's largest city and a once-bustling commercial hub, scenes of people searching through big rubbish bins are now commonplace. They are collecting plastic bags and other flammable material they can use to warm themselves in the chilly Syrian winter.
Abu Mohammad is a lieutenant who defected from the government army and is now based at a military clothing factory taken over by the rebels, in the city's war-scarred Dahret Awwad district. On his way to work, he often saw a woman in her 40s searching through a bin near the factory for something to feed her oil heater.
"One day I saw her struggling to find anything she could use to warm her children. So I brought her a blanket and a pair of torn military boots from here," the 29-year-old told Al Jazeera.
Rebels found hundreds of military tents, blankets and thousands of black military boots when they took over the rusty army compound during a major battle between government forces and opposition fighters in July.
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The dirty boots could not be worn because they were damaged, but the nylon-covered footwear could be burned.
"The woman came back the next day. She asked for another pair of boots. She said they were great for heating," Abu Mohammad said. "The sole of the boots [made of reinforced plastics] were the best part. They kept burning for hours. They were better than wood."
Since fighting erupted in the city last year, prices of heating oil and gas have skyrocketed. A gas cylinder cost 600 Syrian pounds ($8.45) before the uprising began in March 2011, but now fetches 4,500 pounds ($63). The price of heating oil has risen from 15 pounds ($0.21) per litre to 100 pounds ($1.41) per litre. When it comes to electricity, people living in rebel-held areas consider themselves lucky when they receive it for more than two hours a day.
Residents have had to rely on alternatives to traditional fuel to stay warm as temperatures drop to near zero degrees Celsius at night. Some have cut down trees on swathes of land between the city and its suburbs for firewood. And after rebels gained control of an oil field in eastern Raqqa province, many have been buying unrefined petrol from opposition fighters at rates much cheaper than proper fuel.
"The need is the mother of innovation," Abu Mohammad explained.
Today, boots originally made for the government soldiers now shelling rebel-held neighbourhoods have become a means to keep families in these areas warm.
Abu Mohammad said he has already distributed hundreds of boots to households in need. "Every few days, I borrow a truck that belongs to [rebel battalion] Ahrar al-Sham or whoever wants to lend me one. I fill it with boots and go to distribute them in al-Sukkari and other impoverished neighbourhoods," he said.
"Come with me in a few days to al-Sukkari and you will see that by the time I park the truck, a long queue will have been formed of people waiting to receive boots," he told Al Jazeera.
"Only God knows what chemicals come out of these boots. People have been using coal, wood, unrefined petrol and all kind of stuff to warm themselves."
- Abu Mohammad
Huge piles of military boots remain in the factory's courtyard, which has been targeted by the government army's rockets several times since rebels seized it.
"The distribution has been a bit slow. I have to do it by myself to make sure the boots get delivered to the people who need them. Especially after I discovered that some people are selling boots for 25 pounds [$0.35] each," the lightly bearded former lieutenant said.
Abu Mohammad seemed to be excited by the fact that he is helping people stay warm, but when asked about the potentially harmful fumes from the burning of boots, he said: "Only God knows what chemicals come out of these boots. People have been using coal, wood, unrefined petrol and all kind of stuff to warm themselves. So this doesn't matter."
Reports of suffocation
However, reports of suffocation as a result of inhaling carbon monoxide have increased this winter, according to medics in Aleppo. Maryam, a 23-year-old nurse in a field hospital, told Al Jazeera that some of the cases were deadly.
Sitting in the makeshift patient room, once a small clothing shop in a busy shopping district, Maryam said: "A lot of people came to us with cases of suffocation, nausea or poisoning due to inhaling large amounts of carbon monoxide in closed spaces.
"We ask them to keep windows open, but they say the weather is freezing. This leaves a lot of residents in Aleppo with a choice between two basic needs: staying warm or breathing clean air."