Federal officials have given Bank of America Corp. $20 billion more in bailout money and have guaranteed the bank against some $100 billion in mortgage loan losses. Meanwhile, the bank reported a net loss of $1.79 billion in the fourth quarter. That compares to net income of $268 million a year earlier.

The latest assistance from the U.S. Treasury Department and the Federal Deposit Insurance Corp. comes amid growing concerns about the bank’s financial condition. In particular there have been reports that BofA has found losses in Merrill Lynch & Co., which it acquired Jan. 1, that are worse than expected.

Federal officials announced the deal early this morning. After the bailout news, Bank of America reported its harsh earnings report.

The net loss applicable to common shareholders was $2.39 billion, or 48 cents per diluted share, down from net income of $215 million, or 5 cents per share, in the same period in 2007. The results include Countrywide Financial, which BofA purchased on July 1, but not Merrill Lynch & Co. Inc., which was acquired on Jan. 1.

The bank says fourth-quarter results were driven by escalating credit costs, including additions to reserves, and significant writedowns and trading losses in the capital markets businesses.

These actions reflect the deepening economic recession and extremely challenging financial environment, both of which significantly intensified in the last three months of 2008, the bank said in a release,

Global Consumer and Small Business Banking and Global Wealth and Investment Management were profitable, paced by Bank of America’s successful and expanding deposit business. Negative results in Capital Markets and Advisory Services masked the profitability in business Lending and Treasury Services within Global Corporate and Investment Banking.

Merrill Lynch preliminary results indicate a fourth-quarter net loss of $15.31 billion, or $9.62 per diluted share, driven by severe capital markets dislocations.

The additional $20 billion from the government makes BofA the largest recipient of federal cash during the $700 billion Troubled Asset Relief Program adopted last year by Congress. Bank of America got $15 billion from that program in October. When it bought Merrill, it got the $10 billion that was slated to go to the investment bank. With the latest injection, the bank will have gotten $45 billion. Citigroup (NYSE:C) had been the largest recipient.

The government will get preferred stock with an 8 percent dividend for its latest investment. In addition to the $20 billion, the government will guarantee BofA against losses on a pool of $118 billion in residential and commerical real estate loans.

Charlotte-based BofA will be responsible for the first $10 billion of losses. After that the government will assume 90 percent of the additional losses.

The bank’s stock fell 18 percent Thursday as rumor of the financial problems and likely federal action spread.

BofA’s stock, which has traded between $10.01 and $45.08 over the last year, closed at $8.32 per share Thursday, down from Wednesday’s closing price of $10.20.