Bloomberg BusinessWeek reports that CKE Restaurants Inc., operator of the Carl’s Jr. and Hardee’s fast-food chains, said it will sell itself to an affiliate of Apollo Management LP for $12.55 a share in cash, or about $694 million.

CKE terminated a previous merger agreement with affiliates of Thomas H. Lee Partners LP, it said in a statement today. THL Partners, which owns a stake in Dunkin’ Brands Inc., had offered $11.05 a share.

CKE said on April 7 it had received a rival proposal from a then-unidentified bidder that may top the bid it had accepted from THL Partners in February. The acquisition by Apollo affiliate Columbia Lake Acquisition Holdings Inc. shows private equity firms are interested in restaurant chains because of their relatively low debt and good cash flow, said R.J. Hottovy, a restaurant analyst at Chicago-based Morningstar Inc.

Apollo spokesman Charles Zehren declined to comment. CKE spokeswoman Beth Mansfield and THL Partners spokesman Matt Benson didn’t return messages left after-hours at their offices.

CKE has 3,141 restaurants in 42 states and 14 countries, including 1,224 Carl’s Jr. restaurants and 1,905 Hardee’s sites. Founder Carl Karcher borrowed $311 to buy a Los Angeles hot-dog cart in 1941 and became a pioneer in the industry, introducing salad bars, char-broiled chicken-breast sandwiches and self- service beverage stations. He died in 2008.

Related reading at CKE Reastaurants Says New Takeover Bid is Better