Two people were hospitalized with burns after an explosion early Friday at Camp Hope.

Spokane police officers responded to the homeless encampment shortly after midnight after hearing an explosion, according to police. They discovered smoke and a large fire coming from the northwest corner of the camp, which sits on property owned by the Washington state Department of Transportation in the East Central area along Interstate 90.

A tent was fully engulfed in flames and propane tanks shot up into the air, police said. Officers treated two people who were in the tent at the time of the explosion before medics took over. A female sustained significant burns and a male was also burned, officers said. Both were taken to an area hospital.

The Spokane Fire Department extinguished the fire, which investigators said was human-caused and accidental.

The investigation revealed the two people who were burned were transfilling propane tanks in the tent where a propane heater was already operating. Propane leaked out while transferring the gas, filling the tent with it and causing the explosion and fire.