NEW YORK (Bloomberg) — Hartford Financial Services Group Inc., the insurer that got an investment from Germany's Allianz SE this month, reported its first unprofitable quarter in five years as it wrote down the value of stakes in financial firms.

The third-quarter net loss of $2.63 billion, or $8.74 a share, compares with a profit of $851 million, or $2.68, in the same period a year earlier, the insurer said in a statement. The loss was within the company's forecast on October 6, when it cut its dividend and said Allianz, Europe's biggest insurer, would invest $2.5 billion to shore up capital.

"This was an extremely difficult quarter for the company," chief executive officer Ramani Ayer said in the statement. "Volatile credit and equity markets and the largest catastrophe in the past three years significantly affected our results."

Hartford shares have fallen by more than half this month on concern that the Allianz investment may not be enough to cover losses on corporate debt and mortgage-backed securities. Rivals including MetLife Inc., Prudential Financial Inc. and Allstate Corp. have sold stock, halted share buybacks or given cash infusions to their insurance units as the value of their investments slid.

Hartford, based in the Connecticut city of the same name, fell 85 cents, or 4.3 percent, to $19.01 in late trading in New York after the results were released.

US life insurers reached out to Treasury officials last week in hopes of securing some of the $250 billion set aside to prop up ailing financial companies. Some of the firms asked the government to make participation mandatory because they don't want to identify themselves as needing government intervention, said an industry official with knowledge of the discussion.

Hartford spokeswoman Shannon Lapierre declined requests yesterday and earlier this week to comment on whether the insurer would ask the government for funds.

Book value, the measure of Hartford's assets minus liabilities, fell 25 percent over three months to $41.80 a share. The decline was driven in part by $2.2 billion in investment losses.

The majority of the write-downs were related to the company's investments in financial firms, the company said. Last month the insurer said in a separate statement it held $511 million in preferred stock of mortgage lenders Fannie Mae and Freddie Mac and more than $260 million of stock and debt in bankrupt Lehman Brothers Holdings Inc. and American International Group Inc., which ceded majority control to the government in September.

Lehman's bankruptcy and AIG's government bailout roiled credit markets, pushing down the value of insurers' portfolios.