CHICAGO (Bloomberg) — Tribune Co., the second-largest US newspaper publisher, may receive offers from at least five bidders for all or part of the company.Private equity firms including Bain Capital LLC and Apollo Management LP put in bids for the entire company, as have Californian billionaires Ron Burkle and Eli Broad, according to people familiar with the process. Gannett Co. put in a preliminary offer, the Chicago Tribune reported.

Tribune has also approached News Corp., Hearst Corp. and Dean Singleton’s MediaNews Group Inc., the Wall Street Journal reported. Maurice R. Greenberg, former chairman of American International Group Inc. is considering an offer, the New York Times reported yesterday.

“Everybody seems to be showing up,” said Edward Atorino, an analyst at Benchmark Co. in New York. He has a “buy” rating on Tribune stock. “These are very attractive assets.”

The interest in Chicago-based Tribune’s assets, which include the Los Angeles Times and 25 television stations, has increased since Tribune indicated to bidders that it would be willing to sell the company in pieces, rather than as a whole. Tribune chief executive officer Dennis FitzSimons agreed to consider selling the company after pressure from its largest shareholder, the Chandler family.

Shares of Tribune, also owner of the Chicago Tribune and the Chicago Cubs baseball team, are down 34 percent in the past three years after FitzSimons failed to stem the defection of readers and advertisers. Tribune spokesman Gary Weitman didn’t immediately return a call seeking comment.

The bids from investors such as Burkle’s Yucaipa Cos. and Broad’s investment firm helped revive a sale process that slowed after bids from private equity companies came in below the company’s projections.

Boston’s Bain and New York’s Apollo bid about $32 a share, giving no premium to the company’s stock market value. Bids also came from a group consisting of Thomas H. Lee Partners LP, also based in Boston, and Fort Worth’s Texas Pacific Group. Apollo was joined in its bid by Madison Dearborn Partners LLC of Chicago and Providence Equity Partners Inc., based in Providence, Rhode Island.

McLean, Virginia-based Gannett, the largest US newspaper owner and publisher of USA Today, would be the first newspaper company to join the bidding. As well as concerns about the tax bill for Tribune associated with selling individual assets, Gannett may be blocked by media ownership rules, the Journal said.

“Gannett is not a big-city newspaper publisher, it’s out of character for them,” Atorino said. “They may be looking at pieces, certainly the broadcasting.”

Circulation at Tribune’s two biggest newspapers, the Los Angeles Times and Chicago Tribune, has dropped as the company attempts to complete the sale.

Average paid circulation Mondays through Fridays fell eight percent to 775,766 at the Los Angeles Times in the six months ended September 24, according to the Audit Bureau of Circulations. Chicago Tribune’s average weekday paid circulation declined 1.7 percent to 576,132.

The Los Angeles Times is also beset by internal wrangling. Tribune ousted editor Dean Baquet last week, a month after the departure of publisher Jeff Johnson, amid a battle over job cuts.

In response to Baquet’s dismissal, more than 400 Times reporters, editors and business-office workers petitioned Tribune not to force further newsroom job cuts on its 940-person newsroom staff.

Tribune reached out to News Corp., which may be interested in buying New York’s Newsday, the Wall Street Journal said, citing unnamed people familiar with the matter.

Greenberg, 81, has talked to investment bankers and lawyers about an offer for Tribune, the New York Times reported yesterday, citing people briefed on his plans. Greenberg, who has amassed a fortune of more than $20 billion, is also interested in pursuing other newspapers such as The Boston Globe and possibly Dow Jones Co., publisher of the Wall Street Journal.

MediaNews has had informal talks with Tribune about buying the Hartford Courant and Stamford Advocate in Connecticut, the Journal reported, citing one person familiar with the matter. Tribune initiated those talks, the newspaper said.

Joseph Lodovic, president of MediaNews, didn’t return a call seeking comment. Paul Luthringer, a spokesman for Hearts, declined to comment.