The animals broke into a sports store at an Austrian ski resort.
A spokesperson for the Intersport shop in St Anton said: "We think one of them saw its reflection in a mirror and came in to investigate.
"And being sheep, of course the rest of them decided to follow."
The shop's owner is now negotiating with the owner of the flock over the thousands of pounds' worth of damage that was done.
A similar incident occurred last year when a cow invaded another branch of the sports store.
The animal became a star when she was featured in the company's TV adverts.
Her owner Hans Schroder had the expensive task of paying for everything that the cow trampled on and ate.
"I had to buy everything - even the bras Laura chewed," he said.
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