For more than two years, Joseph Mifsud, the man who triggered the Russia investigation, has been MIA.

In recent weeks, his name has resurfaced as a critical subject in U.S. Attorney General William Barr and prosecutor John Durham’s criminal probe.

Nonetheless, his location has been a mystery – until perhaps now.

On Wednesday, Italian publication Adnkronos published audio -- sent to them in two separate encrypted files -- claiming to be Mifsud and taped on November 11.

"I have absolutely no contact with friends and family for several months,” the voice in the audio claims. “It has been almost two years now that the whole matter has exploded and been presented to the world media and on the world stage as if I had something to do with matters concerning countries or had I tried to infiltrate it, it is absolutely absurd, in programs, contacts or any other institution in the world. I have been a man of relationships all my life and this is what I do well."

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Although Fox News could not independently verify, some who knew Mifsud, 59, said they believed the voice to be authentic. His lawyer, Stefan Roh, expressed skepticism given that much of the recording was centered on Mifsud insisting he did not work for "any service, secret service or intelligence or none of this kind."

The voice stresses that he was under "no pressure" to go dark, but he did at "suggestion from friends," adding the situation has become "almost too much to bear."

Over the weekend, tweets by former Trump campaign aide George Papadopoulos and his wife Simona, who briefly worked for Mifsud, indicated he was being harbored by Western intelligence agencies.

But who is the mysterious Maltese Professor? Who is hiding him and who is he hiding from?

It was in March 2016 when newly installed Trump aide Papadopoulos traveled to the Link University campus in Rome to meet Mifsud, touting his Kremlin connections.

On April 26, just after Mifsud returned from an energy conference in Moscow, he met Papadopoulos for a breakfast meeting and mentioned that the Russians have “dirt” on Hillary Clinton, in the form of “thousands of emails.”

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But Mifsud’s much-boasted Russian connections were mostly non-existent, Papadopoulos has since claimed. Almost two weeks later, Papadopoulos commented that the Russians had damaging Clinton information during a meeting with Alexander Downer, an Australian diplomat and former board member of private MI6-founded intelligence firm Hakluyt & Co.

The information was not passed on through official channels straight away. In late July 2016, after the first trove of WikiLeaks DNC emails swarmed the Internet, Downer shared his tip, which was then used by U.S. authorities and as evidence to open Crossfire Hurricane, the code name for the FBI’s investigation into links between Trump associates and Russian officials.

Fast forward to 2019, no official has concluded exactly who Joseph Mifsud is, despite him being highlighted in Robert Mueller’s final report 89 times.

No birth date is publicly listed for him, other than he was born in Malta in 1960.

He took a position in Malta’s Ministry of Foreign Affairs from 2006 to 2008 as the private secretariat of minister Michael Frendo. During that time, Frendo was photographed in Australia with his counterpart, then-foreign minister Downer. Frendo did not respond to requests for comment regarding whether his press aide, Mifsud, also met Downer.

Mifsud then became president of Slovenia’s Euro-Mediterranean University (EMUNI). He left in 2012, allegedly owing the university more than $43,000 in expenses that far exceeded the compliance limit.

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Mifsud was later appointed director of the London Academy of Diplomacy (LAD), affiliated with Scotland’s University of Stirling. Much of Mifsud’s work, across Europe and the U.S., pivoted on exchange programs and setting up partnerships between universities. But several bemoaned he did not follow up after initial meetings.

Although his name no longer appears on the membership roster, as of at least March 30, 2016, Mifsud was as a member of the prestigious European Council on Foreign Relations (ECFR), which is comprised of former prime minister, foreign ministers and dignitaries from around the world.

At that time, Mifsud was also professionally affiliated with Link in Rome. Yet his exact role at the so-called “spy school” campus – in which Papadopoulos was first encouraged to meet him – is also blurry.

The president of Link, Vincenzo Scotti – who served as Italy’s Minister of the Interior and then as Minister of Foreign Affairs – told Fox News that Mifsud “participated in Link events because he was considered an expert,” not as a professor.

Mentions of him have been scrubbed from Link’s website, yet archived versions list him as a “foreign teacher” who specializes in “comparative policy.”

In late May 2016, Mifsud deepened his own U.S connections and was pictured alongside high-ranking individuals and heads of state at a Doha forum organized by Qatar’s foreign ministry. It was here that he met the then CEO of the State Department-supported Global Ties U.S., Jennifer Clinton, and the two stayed in contact.

In the aftermath of the 2016 election and the heat of the then Comey-led probe, between December 4 and 12, Mifsud traveled to Washington and later on to New York. According to email correspondence obtained by Fox News, Mifsud prescheduled a number of different meetings while in the United States, ranging from the United Nations to OAS to Global Ties.

While in New York, Mifsud met with at least one professor at Columbia University. According to email exchanges viewed by Fox News and dated Dec. 5, 2016, Mifsud was scheduled to discuss “Cooperation with London and Rome” in a private meeting in the Manhattan campus of Columbia University with the senior assistant dean, Urbano Garza.

A representative for Columbia told Fox News that Mifsud met to discuss a possible student exchange between their School of International and Public Affairs (SIPA) and the London Academy of Diplomacy, but that he never followed up after the initial meeting.

During the December 2016 visit, he also met with Clinton and some of the Global Ties team in Washington. Mifsud agreed to come on-board as a speaker for a forthcoming summit, and he returned in February.

Mifsud was neither paid a speaking fee nor was his travel reimbursed, a U.S. Global Ties spokesperson stressed, noting that the event he spoke at was not sponsored by the U.S. State Department. Specifically, Mifsud was asked to be a speaker for a three-hour, Global Ties U.S.-hosted event called the Strategic Dialogue, which was privately funded. Separately from the National Meeting, on the last day was a summit supported by the State Department, of which Mifsud is said to have paid to attend.

The non-profit organization, which advocates for international exchange programs and citizen diplomacy, said none of their team was interviewed by federal investigators with regards to Mifsud.

It was near the end of this U.S. trip, on Feb. 10, 2017, that Mifsud was first interviewed in the lobby of his Washington hotel by investigators.

But life resumed for Mifsud. He attended more ECRF events, was interviewed at the Link-sponsored “G7 International Forum” in Italy in May 2017.

On Oct. 19, 2017, Mifsud’s businessman friend Prasenjit Kumar Singh even took him to a dinner event to meet the then British Foreign Minister, Boris Johnson.

“Joseph was extremely influential and had good connections in the diplomatic circle. He was also a good speaker,” Kumar, who had known him for about six years, said. “(But his) greatest disadvantage was to exaggerate matters and sometimes tell things that are not entirely true.”

Just over a week after the Johnson dinner, on Oct. 30, 2017, the indictment against Papadopoulos for false statements was unsealed – bringing to light an unnamed professor as the one who passed on the “dirt” comment to the then 28-year-old Trump campaign adviser. A few days later, Mifsud’s name was exposed by the Italian press, and he denied ever being an asset for the Russian government.

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Mifsud was last seen at the bar on the Link campus in November 2017 – the morning his identity was exposed – and never returned, Scotti said.

For more than two years now, Mifsud’s whereabouts have remained a mystery.

Laris Gaiser, a Slovenia-based crisis consultant who was brought in to investigate Mifsud’s tenure at the Euro-Mediterranean University (EMUNI), told Fox News on Wednesday that the professor was staying in a small village in Italy's Esanatoglia region, as confirmed by Antonio Grizzuti and Giacomo Amadori of La Verita who spoke to neighbors, a home owned by the managing company of Link. Mifsud was known to have the occasional drink until again disappearing at the end of 2017.

Roh, the Swiss-based, German attorney for Mifsud, told Fox News that he had direct contact with Mifsud up until the end of October 2018, and maintained indirect contact – through a family member – until the Spring of this year when the Mueller report was released.

“The family member I usually talked to is not reachable to me anymore. We are now more concerned about his well-being than before. A single person cannot hide in Europe or such a long time,” Roh said. “In particular, as the world is searching for him. There must be an organization hiding Professor Mifsud.”

His last in-person meeting, Roh said, was in May 2018 when a frightened Mifsud traveled – by train to avoid having to use his passport or identification – to Roh’s law firm office in Zurich and recorded a testimony addressing the scandal.

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Roh remains adamant that Mifsud was not connected to the Russian government, his connections to the country being only in an academic sense.

Released in April 2019, the Mueller report stated that Mifsud gave “false statements” to federal investigators.

In an op-ed for the Washington Post in May, former FBI Director James Comey went so far as to imply that Mifsud is a “Russian agent,” but the characterization seems not to have ruffled broader feathers.

When asked in July, during the first round of Mueller’s testimony before the House Judiciary Committee, why Mifsud was not charged with a crime despite statements that he lied three times to investigators, Mueller declined to answer.

Some legal experts find the response unsatisfactory.

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“If he was a Russian asset all these years, it would be a troubling statement about American intelligence and diplomacy,” added Kendall Coffey, a former U.S. Attorney for the Southern District of Florida. “A Russian spy working for many years with the State Department, the CIA, and British and Italian agencies? It seems unlikely, to say the least.”