Shares of AIG, the beneficiary of a $180 billion U.S. government bailout, rose as much as 10 percent on Monday morning, extending strong gains last week, as the insurer returned to a profit in the second quarter, ending a six-quarter run of losses.

Shares rose as high as $29.88, or 10 percent on Monday, after doubling in value last week, as investors applauded unrealized investment gains that pushed it back into the black.

Wells Fargo raised its price range for the shares to between $21 and $29, from $14 to $18.

Analyst John Hall, in a research note on Monday, said he believed the company would remain a going concern following the Federal Reserve bailout.

Still, there are risks to holding the stock, he said, including assets having to be sold for too little, losses from disasters such as hurricanes and earthquakes, and any further problems in retaining customers.

American International Group's insurance units posted weaker results in the quarter, attributing the decline in business to the economic downturn. It noted that some customers have grown more wary since the company nearly had to file for bankruptcy last September.

Once the world's largest insurer, AIG nearly collapsed from credit default swaps that left it on the hook for tens of billions of dollars in payouts to some of the biggest U.S. and European banks. As a result of its bailout, the government now owns about 80 percent of the insurer.

The company's new chief executive Robert Benmosche takes over on Monday, becoming the fourth person to assume AIG's leadership since June of last year.

The stock was up more than 7 percent at $29.14 in mid-morning trade on the New York Stock Exchange.

(Reporting by Lilla Zuill; Editing by Derek Caney)