CHICAGO — Chicago Sun-Times film critic Roger Ebert duelled with Conrad Black, the ousted CEO of the newspaper's parent company, in a series of sharply worded letters published Wednesday.

Ebert said he felt betrayed by allegations that the Canadian-born newspaper mogul used Hollinger International profits for personal expenses while the Sun-Times building sat in disrepair and union employees threatened to strike over wages and benefits.

Black scoffed at Ebert's "ingratitude,'' citing the critic's $500,000 salary.

The exchange, published in the Sun-Times commentary section, began earlier this month when Ebert, co-host of Ebert & Roeper and the Movies, wrote in an open letter to publisher John Cruickshank during contract negotiations that he would not cross a picket line if the paper's staff went on strike.

He complained about reports of "millions of dollars winging away to the (former chief operating officer David) Radler and Black billfolds while we worked in a building where even basic maintenance was ignored.''

Black was ousted as CEO of Hollinger International Inc. late last year amid an internal investigation that accused him, Radler and others of systematically looting the newspaper publishing company of more than $400 million -- nearly all its profits from 1997 through 2003.

A special committee of Hollinger International's board said Black had Hollinger pay for things like $8.9 million worth of Franklin Delano Roosevelt memorabilia while Black was writing a book about FDR. The company also financed nearly $25,000 for "summer drinks'' and more than $42,000 for a birthday party for Black's wife, Barbara Amiel Black.

Black and Radler have denied doing anything improper.

In his letter, Black reminded Ebert it was the "generous treatment from David Radler'' that was responsible for his $500,000 salary and other compensation.

At the end of his letter, Black wrote that "your proletarian posturing on behalf of those threatening to strike the Sun-Times and your base ingratitude are very tiresome.''

Ebert replied: "Since you have made my salary public, let me say that when I learned that Barbara received $300,000 a year from the paper for duties described as reading the paper and discussing it with you, I did not feel overpaid.''

The internal investigators said Amiel Black was paid "more than $1.1 million a year in annual salary and bonus payments'' and "she performed no meaningful work in return.''

At the same time, Ebert wrote, escalators in the Sun-Times building "were actually turned off to save on electricity and maintenance.''

The Sun-Times reached a tentative contract deal with unionized reporters, editors and other news staff last week, about two hours after a strike deadline.