LOS ANGELES — General Growth Properties Inc. said a $10 billion takeover offer from rival Simon Property Group Inc. is too low and it will invite others to make bids as it considers options for emerging from bankruptcy.

General Growth, whose Hawai'i properties include Ala Moana Center and Ward Centers, plans to provide financial projections, data on its shopping malls and other information to those interested in making bids. Materials likely will be sent out by the beginning of next month, with indications of interest due back within four weeks, the Chicago-based mall owner said yesterday in a statement.

"We believe the information we would provide to you as part of this process will enable you to better understand the company, get to a higher valuation, and provide a fully documented offer," General Growth chief executive Adam Metz said yesterday in a letter to Simon chairman and CEO David Simon. The letter was included in General Growth's statement.

Simon offered to buy General Growth for more than $10 billion and combine the biggest U.S. mall owners. About $9 billion of the bid is in cash, Indianapolis-based Simon said in a statement yesterday. General Growth shareholders would get about $9 a share, including $6 in cash, and unsecured creditors would be repaid in full for about $7 billion. Simon said it made its offer public after receiving "no substantive" response from its rival.

General Growth shares rallied above the offer price, climbing 28 percent to $12.02 in over-the-counter trading at 4 p.m. New York time. William Ackman's Pershing Square Capital Management LP said in December that the company was undervalued and may be worth $23 to $43 a share.

"Given what this is going to give Simon, they can afford to pay more," said William Acheson, equity analyst at New York- based Benchmark Co. "They will have a lock on the best malls in the best markets in Boston, New York and some of the bigger California cities."

Ackman, whose firm owned 7.5 percent of General Growth's shares as of December, declined to comment on Simon Property's offer, citing his position on General Growth's board.

General Growth filed the biggest real-estate bankruptcy in U.S. history in April after amassing $27 billion in debt during an acquisition spree.

In the filing, the company said it had about $11.8 billion in debt that had matured or was due by the end of 2012.

David Simon said at the time that he had tried to buy some of the company's properties.

General Growth's best-performing malls are the Grand Canal Shoppes and Fashion Show in Las Vegas, Ala Moana Center in Honolulu, and Whalers Village in Lahaina on Maui, according to Green Street. All four have annual sales per square foot of $1,100 to $1,200.

General Growth's other malls include Boston's Faneuil Hall and South Street Seaport in New York City.