LONDON, Ont. -- Fire officials in London say a passer-by on a bicycle helped prevent a backyard fire from engulfing a couple's home.

Fire inspector Denise Rose says Kevin Cambridge was out for a bike ride Sunday afternoon when he heard calls for help and stopped to lend a hand.

Rose says the blaze started when a barbecue accident set a backyard shed on fire.

She says Cambridge helped the homeowners get away from the fire, and got their two dogs to safety -- a rescue pulled off while he was calling 911 on the owners' phone.

He then tried to put out the fire with a garden hose while firefighters made their way to the scene.

Rose says that without Cambridge's help the fire in the shed would have spread to the house itself.

"It was significant," she said of the cyclist's actions to contain the blaze.

"If water hadn't been put on the shed, the fire would have caught the house," she said.

A fire platoon chief said the fire caused an estimated $50,000 in damage.