The chairman of the U.S. House of Representatives subcommittee on economic and consumer policy sent a letter on Tuesday to major U.S. meat processing companies, seeking information on rising prices and profits.

The companies included Tyson Foods, JBS Foods , National Beef and Seaboard. Representative Raja Krishnamoorthi, the chairman of the panel, asked for information about price increases on beef, pork and chicken products, the panel said on Tuesday.

"While some companies may claim that the high prices feeding these outsized profits are explained by higher input costs, earnings data tell a different story," Krishnamoorthi said on Tuesday.

"I am deeply concerned that meat processing conglomerates may have engaged in predatory business practices, at the expense of consumers, during the pandemic," he added.

Krishnamoorthi has asked for information and documents from each company by Feb. 8, explaining their decision to increase prices of their products despite rising profits. He also asked for an explanation from the companies on what they planned to do to lower prices in the coming year.

He said that net profit margins for the four biggest meatpacking companies have shot up over 300% since the start of the coronavirus outbreak and accused the companies of increasing their profits "at the expense of the American families."

White House economics advisers said last month that the biggest meat-processing companies, using their market power in the highly consolidated U.S. market to drive up meat prices, have tripled their own net profit margins since the COVID-19 pandemic started.

The White House, hammered by Republicans over rising inflation, is scrambling to combat rising prices by clearing supply chain logjams and tackling what it views as uncompetitive practices by big companies, which are reporting big profit gains as consumers suffer.