Flaming lithium-ion battery forces two to leap from San Francisco building

Fire broke out in a Sunset District apartment, injuring five.
Two residents jumped from windows to escape the blaze that started from an exploding lithium-ion battery.
Three people were taken to the hospital with injuries and five to eight displaced from their homes.
The fire caused heavy damage to one unit and moderate damage to another in the multi-unit building.
The cause of the fire remains under investigation though lithium-ion batteries can be highly flammable.