The Department of Justice now wants to know whether eight of the country’s largest grocery retailers can be blamed for it.

Federal investigators are scrutinizing Walmart, Costco, Amazon, Kroger, Publix, Albertsons, Aldi and Ahold Delhaize USA for beef affordability, with the DOJ calling beef prices a “priority” for the agency in a Sept. 1 X post announcing the probe. The retailers and the DOJ did not respond to Fortune’s requests for comment.

The Trump administration has zeroed in on tamping down beef prices, as the cost of staples like ground beef shape how consumers judge inflation, a key issue for voters ahead of the midterms.

The new probe into retailers seems to build on the department’s antitrust investigation into meatpackers that launched in May.

Trump asked the DOJ to probe meatpackers over beef prices in November, accusing them of “driving up the price of Beef through Illicit Collusion, Price Fixing, and Price Manipulation.” He scrapped 40% tariffs on Brazilian beef the same month, and announced last month a plan to allow 300,000 metric tons of it into the country without being subject to out-of-quota tariffs.