His son Sean said the cause had not been determined.

Dunleavy relished his role as a mouthpiece for media mogul Rupert Murdoch, working for him as a writer and editor at the celebrity-filled Star magazine; as an editor and right-wing columnist at The New York Post; and as the lead reporter for the tabloid-like TV newsmagazine “A Current Affair” (now off the air) on Fox.

Dunleavy exposed Elvis Presley’s addiction to prescription drugs in Star and in a bestselling book that rankled Presley fans; scored exclusive interviews with the mother of Sirhan Sirhan, Robert F. Kennedy’s assassin, and Albert DeSalvo, the confessed Boston Strangler; and championed police officers, smokers and gun owners, among others.

During his run on “A Current Affair,” from 1986 to 1995, he wrestled a bear in one segment and, in another, was bitten by a witness in a rape case when he confronted her with nude photographs of her.

His tenure on TV was sandwiched between two stints at The Post, which Murdoch bought in 1976. As metropolitan editor, Dunleavy rekindled a circulation war with The Daily News when the two tabloids vied for scoops while David Berkowitz, otherwise known as Son of Sam or the .44-caliber killer, was terrorizing New York in 1976 and 1977.

“As a reporter, metropolitan editor and columnist for this paper,” The Post said in an editorial published online Monday, “the charismatic, swashbuckling Dunleavy helped turn a once-sedate tabloid into a roaring must-read that New Yorkers loved or hated — or both.”

Dunleavy had expressed the hope that he would die at his desk, but he retired in 2008 because his legs were giving out.

He was said to have been the model for Wayne Gale, the manic Australian reporter played by Robert Downey Jr. in Oliver Stone’s 1994 film “Natural Born Killers.” But he gravitated closer to the Runyonesque characters in Ben Hecht and Charles MacArthur’s play “The Front Page” from 1928.

“I lost count of the number of times I posed as a cop, a public servant or a funeral director,” Dunleavy told William Shawcross, the author of a 1993 Murdoch biography.

Dunleavy sneaked into a hospital in scrubs to interview a crime victim’s family, found fugitive financier Robert L. Vesco, and defended several police officers implicated, and convicted, in the sodomizing of a Haitian immigrant, Abner Louima, in 1997. He also defended a Vietnam War veteran who was convicted of rape and who, after he was paroled, raped and murdered two women.

“Mate, I’ve never had a bad day in journalism in my life,” he once said. “You win, you get drunk because you won. You lose, you get drunk because you lost.”

By his own metric, though, he never lost.

After actress Ava Gardner rejected his invitation to be interviewed at a nightclub and threw a glass of Champagne in his face, he wrote an article that began: “Last night, I shared a glass of Champagne with Ava Gardner. She threw it; I wore it.”

He often conducted business from Langan’s, a bar on West 47th Street in Manhattan, around the corner from The Post’s offices at the time. There, he huddled in a booth near the men’s room chain-smoking Parliament lights (before the ban) and gulped vodka and tonic.

His Aussie brew of glitter and grit baited fellow journalists, who sometimes concluded that Dunleavy not only covered the news, but also made it.

“Dunleavy does not take food with his meals,” reporter Charlie Leduff wrote in The Times after interviewing Dunleavy at Langan’s in 2001.

“Regardless of the number of drinks he has ingested, no matter how slurred his speech,” he continued, “he has the curious ability to pan nuggets of gold from the pond of his intellect and extemporaneously recite them to his editor.”

In a New Yorker profile titled “The Hell-Raiser,” John Cassidy described Dunleavy as “smartly dressed, in a gray three-piece suit, white monogrammed shirt with French cuffs, gold cuff links, red silk tie, and shiny black shoes.”

“His pallor was that of a rotting cod,” Cassidy went on. “His silver pompadour, which makes him resemble an aging Elvis impersonator, shot from his crown in glorious defiance of taste and gravity.”

If Dunleavy exhibited a certain sartorial dash, he professed never to put on airs. He called journalism “a craft, like being a master plumber.”

“We wore white collars,” he said of his generation of reporters, “but we were blue collar.”

Stephen Francis Patrick Aloysius Dunleavy was born Jan. 21, 1938, in Bondi Beach, at the time a working-class suburb of Sydney, to Steven and Dorothy Dunleavy. His father was a photographer for the Sydney tabloid The Sun. Steve quit school and went to work for the paper as a copy boy when he was 14.

Two years later, he was hired as a cub reporter by the rival Daily Mirror, where, legend has it, he deflated the tires on his father’s car so that The Mirror’s photographer would get to the scene of a story first.

Dunleavy freelanced in Asia and Europe, worked for United Press International in London, goofed around in the Bahamas and, in late 1966, arrived in New York (with either $7 or $10 in his pocket). Hired full time by UPI, whose offices were in The Daily News Building, he soon met Murdoch, whose Australian papers’ news bureaus were also housed there. He would work for Murdoch for the next 41 years.

Dunleavy’s first wife, Yvonne Dunleavy, was a writer who had a hand in the 1971 bestseller “The Happy Hooker: My Own Story,” by Xaviera Hollander. The marriage ended in divorce.

His survivors include his second wife, Gloria, a retired real estate agent, whom he married in 1971, and their sons, Peter and Sean.

Dunleavy was hired in 1967 to write for Murdoch papers in Britain and Australia. He was named Star’s news editor when it was launched in 1974.

His columns in Star typically echoed the company’s conservative line, so much so that they earned him the “American of the Year” award from the right-wing John Birch Society — even though he was not a United States citizen and never became one.

For all his rakishness, Dunleavy won the affection and even the respect, sometimes begrudging, of many colleagues.

“In a time of listless reporting, he climbed stairs,” Daily News columnist Jimmy Breslin once said. “And he wrote simple declarative sentences that people could read, as opposed to these 52-word gems that moan, ‘I went to college! I went to graduate school college! Where do I put the period?’ ”

Pete Hamill, who worked for both The Post and The News, was impressed by his drive. “I always thought he was writing his columns like he was double-parked,” Hamill said.

And Stuart Marques, another former colleague, expressed surprise in an email that Dunleavy had lived into his 80s, given the pace of his work and play, at least as those exploits were recounted and, perhaps, embroidered.

“There are a million Steve Dunleavy stories, and they’re all true," Marques said, “even the ones that never happened.”

This article originally appeared in The New York Times.