CNN — Just hours after Twinkies maker Hostess declared it will shut down for good, grocery stores nationwide were already experiencing a run on Twinkies and other iconic products from the company like Wonder Bread, Hostess CupCakes and Ding Dongs.

"We're definitely seeing a sharp increase in purchases of Hostess' products today," said Mike Siemienas, spokesman for grocery store operator Supervalu. "We expect this will continue as more consumers become aware of the news.

Irving, Texas-based Hostess Brands announced Friday that the company had initiated steps to shutter its operations, blaming a strike by bakers protesting a new contract that was imposed on them.

Siemienas said shoppers were snapping up Hostess products off of shelves across Supervalu's network of grocery stores nationwide, including Albertsons, Jewel-Osco, Acme and Shaw's.

"These products are available while supplies last," he said. "But we're now preparing for the fact that we won't have them in the near future."

When Supervalu stores runs out of Twinkies and Ding Dongs completely, Siemienas said the company will fill up the empty shelf space with other private label brands.

At Kmart, company spokeswoman Shannelle Armstrong said the retailer hadn't yet seen an uptick in Hostess Brand purchases. "However, that might change over the weekend," she said.