Astoria Park murder mystery: What’s real reason commie-hunting academic was slain?

When cops arrested a mysterious Queens man for pumping two bullets into the back of the head of historian William Klinger, an expert in the former Yugoslavia’s brutal communist past, the Saturday slaying in Astoria Park was quickly attributed to an Italian real estate deal gone bad.

Klinger, a Croatian national who was living in Rome, was in America by some accounts, to teach. Others say he was only in town for a conference on Yugoslavia.

Police said the 42-year-old Klinger was renting a room from his accused killer, fellow Croat Alexander Bonich.

Bonich told police he felt disrespected by Klinger. “(I) grew angry that this visitor would threaten me and pass rude remarks,” he told police, the Daily News reported.

He said Klinger walked away after arguing. “I told him to stop, but he turned his back and kept walking away,” said Bonich, who was held without bail Tuesday after being arraigned in Queens. “The gun fired. He fell immediately at the foot of the stairs.”

“I fired again, sickened by his behavior,” he added.

A Metro investigation has found that there’s much more to this story, starting with Klinger’s grieving widow and the alleged killer’s identity, which has changed several times through the years.

After cops arrested Bonich, 50, he is said to have confessed he was mad that Klinger had reneged on a promise to sell him his home in Italy.

That’s news to Klinger’s Italian wife, Francesca Boscarol.

“She didn’t know anything about that deal,” a source told Metro.

In Croatia, some of his fellow countrymen believe something else is afoot.

And it is all connected to the longtime Yugoslav dictator, Marshal Josip Broz Tito, whose death in 1980 eventually led to years of instability, wars, and the breakup of the multi-ethnic nation into six states: Bosnia and Herzegovina, Croatia, Kosovo, Macedonia, Montenegro, Serbia and Slovenia.

Klinger was the main force behind “Tito — The Secret Empire,” a series of writings which were to be made into an explosive documentary revealing that Tito’s allies are still very much entwined in the leadership ranks of the various ex-Yugoslav states.

“Klinger’s death is a big loss and a heavy punch for our ambitions,” said Klinger’s partner in the project, Denis Kuljiš.

A Croatian source told Metro that Klinger’s accusations made him the target of “speeches of hate” and sub-rosa whispers that he was “the public enemy and the double agent.”

So how does that all tie him to Bonich, who is expected back in a Queens courtroom Feb. 17.

For one thing, sources say, Bonich is not his original name.

He was born Aleksandar Soldatić. He has also used the name Alex Rudolf de Domini. The mailbox at his Astoria apartment also lists him as Rudy Bonich. Bonich is the surname of a noble family from Croatia’s picturesque island of Rab in the Adriatic Sea.

The Croatian sources add: He has allegedly lied in the past about his ties to CUNY’s Hunter College, about being a member of the Italian community in Croatia’s port city of Rijeka, and about going to high school in that city.

Bonich is believed to have indeed met Klinger in Rijeka at some point, but the nature of their friendship remains cloudy.

Some Croats suspect Klinger may have known some dark secrets about Bonich and his false identities — and perhaps something far more sinister.

The Queens DA listed the suspect’s address as 25-66 42nd Street in Astoria, where he was an even greater mystery.

“Nobody knows him,” a longtime resident said. Another said she hadn’t seen him in three years. Yet another said he was in the apartment one or two months a year and that his octogenarian mother would come now and then to clean the place.

Astoria residents seemed most relieved that Klinger and his confessed killer — who cops traced via area surveillance cameras — were known to each other and that they didn’t have to fear a rogue gunman was on the loose.

The DA’s office said the slaying is still under investigation. Bonich’s lawyer, Harry Ramirez, did not return a call for comment.

Bonich told cops he tossed the antique pistol he used to kill Klinger into the East River.