ST. LOUIS - Panera Bread is buying Au Bon Pain in the reunification of two bakery cafe chains.

“With the acquisition we are announcing today, we are bringing Au Bon Pain and Panera together again," said Panera CEO Ron Shaich in a statement. Shaich co-founded Au Bon Pan more than three decades ago.

Both chains are fast-casual chains known for their sandwiches, salads, soups and pastries. Au Bon Pain currently has 304 locations worldwide, including many in hospitals, universities, transportation hubs and urban office buildings.

The acquisition will enable Panera, a chain that promotes its healthy offerings, to catapult into new types of retail environments, it announced Wednesday.

Panera didn't disclose the terms of the deal. which is expected to close during the fourth quarter. Au Bon Pain officials could not immediately be reached for comment.

Panera CEO Shaich and Louis Kane created Au Bon Pain in 1981 and the company went public a decade later. In 1993, Au Bon Pain acquired the Saint Louis Bread, which was renamed Panera. Six years later, Au Bon Pain was sold off.

Luxembourg-based investment firm JAB, which also controls the Krispy Kreme chain and coffee brands Keurig and Caribou, acquired Panera in July and took the company private.

Last month, Wall Street speculated that JAB wanted to buy Dunkin' Brands, which includes another mighty coffee chain Dunkin' Donuts.

As of late September, Panera had 2,050 locations in 46 states and Ontario, operating under the Panera Bread, Saint Louis Bread Co. or Paradise Bakery & Cafe names.