VANCOUVER -- A fire that left a woman with serious injuries has raised concerns about safety for homeless people as temperatures dip in British Columbia's Lower Mainland.

Chilliwack Mayor Sharon Gaetz says fire crews were called to two separate blazes involving homeless people overnight Tuesday, including one where a woman sustained serious burns and needed to be airlifted to hospital.

She says officials have heard anecdotal reports that the fire started in a tent, but by the time crews arrive on scene "there wasn't much left."

As winter weather rolls in, Gaetz says officials are hearing more reports of people living on the streets who are using candles and propane to keep warm, posing a danger to themselves and to fire crews.

Capt. Jonathan Gormick with Vancouver Fire and Rescue Services says crews confiscated propane-powered cooking devices and space heaters from a homeless camp in east Vancouver on Tuesday because the devices pose serious health and fire risks.

He says firefighters are trying to work with homeless campers to make sure everyone is safe, but can't allow open flames in tents because a single spark could easily set the fabric on fire and pose a danger to an entire camp.