Rumors are swirling about Amazon's interest in buying a brick and mortar retailers. Following last week's report that the e-commerce giant looked at acquiring high-end grocery chain Whole Foods, The New York Post is reporting that Amazon has expressed "moderate interest" in acquiring BJ's Wholesale Club.
BJ's, which was taken private in 2011 for $2.8 billion, is reportedly up for sale after putting aside plans for an IPO. Investors expect BJ's to fetch at least $4 billion for an acquisition. The membership-only wholesale retailer operates over 200 retail warehouse clubs and 130 gas stations across 15 U.S. states. It competes against Sam's Club and Costco.
Get Data Sheet, Fortune’s technology newsletter.
Amazon's interest in a retailer, especially one that sells groceries, isn't particularly surprising. The e-commerce giant has recently been experimenting with a line of convenience and grocery stores called Amazon Go.
Amazon also offers its own online grocery delivery and ordering service, Amazon Fresh, which has been operating since 2007. Amazon Fresh previously cost $299 annually, but the terms of membership were changed in 2016 to include $15 monthly fee on top of the $99 Amazon charges for its marquis subscription service for shipping and content streaming, Amazon Prime. And the company has also been opening up a number of brick and mortar bookstores, including locations in Seattle, San Diego, and Boston.
BJ's would likely be Amazon's largest acquisition to date. The company paid $775 million for robotics company Kiva Systems in 2012 and shelled out $1.2 billion for e-commerce company Zappos in 2009.