When most panicked during the financial crisis, Warren Buffett invested, reaping more than $10 billion, The Wall Street Journal reported Monday.

Tightening credit markets in 2008 caused six major companies to take about $26 billion in loans from Buffett and his conglomerate Berkshire Hathaway, the Journal said.

These investments began with a deal with candy maker Mars, which just repaid Berkshire for a $4.4 billion loan its subsidiary Wrigley took in 2008, the newspaper said, giving Berkshire $680 million in profits. Berkshire's big crisis-era investments also included Goldman Sachs and Bank of America, the newspaper said.

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Buffett's investments compare with the U.S. government's $420 billion investment in struggling companies through the Troubled Assets Relief Program.

"In terms of simple profitability, an average investor could have done just as well investing in the stock market if they bought during the panic period," Buffett told the Journal on Saturday. "You make your best buys when people are overwhelmingly fearful."

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To read the Journal's full story, click here.)

—By CNBC.com