Two teenagers face arson charges after a fire destroyed a supermarket, prompting the evacuation of a shopping centre near Adelaide.

More than 100 firefighters were called to the blaze inside a Woolworths store at Stirling in the Adelaide Hills on Sunday afternoon.

Videos on social media showed people running out of the supermarket at the Stirling Village shopping centre, as large flames filled the air and alarms blare.

No injuries were reported, and the fire was brought under control late rin the afternoon.

SA Police said the supermarket was completely destroyed and several other businesses were significantly damaged.

Authorities initially said the damage bill was expected to be about $15 million, but revised it to be in excess of $25 million.

SA Country Fire Service executive director of operations Cameron Devey said there were reports that aerosol canisters were exploding before firefighters arrived at the scene.

Fire Cause Investigators were back on the scene on Monday to try to determine the exact cause of the blaze.

Mr Devey praised the swift response by volunteer firefighters.

“When they first arrived they made every effort to get inside but that fire was just too hot to do anything with so they went defensive and fought the fire from outside,” he told the ABC.

“There will be smoke damage to neighbouring business, there could be water damage and the saves were incredible because that fire could have been so much worse.

“Our volunteer firefighters are part of the community and our hearts go out to everybody today who won’t be turning up to work to businesses that are impacted.”

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Two 14-year-old boys from the Adelaide Hills were arrested and will be charged with arson, police said.

They will be granted bail to appear in the Mount Barker Youth Court at a later date.

Firefighters had earlier said the blaze was generating thick smoke, and recommended people on Mount Barker Road and surrounding streets keep their doors and windows closed.

-with AAP