The self-described “strategic intelligence” firm Fusion GPS that was behind the controversial anti-Trump dossier has a track record of intimidation and smear tactics, according to congressional testimony and the firsthand account of a London-based Venezuelan journalist who said he was labeled a “pedophile,” “extortionist” and “drug trafficker” after criticizing one of Fusion’s clients.

“I believe that Fusion GPS’s business is to do basically whatever the paymasters tell them to do,” Alek Boyd, the Venezuelan journalist, told Fox News in his first American TV interview. “They are particularly good at spreading misinformation, disinformation and smears.”

Boyd says he was targeted after his 2012 reporting on Derwick Associates, a power company with close ties to the Venezuelan government. The company allegedly skimmed nearly a billion dollars from rigged contracts with the late Venezuelan dictator Hugo Chavez.

“It is my understanding that [Fusion GPS] were hired basically to smear Derwick opponents and to dispel any possible doubts that regular media may have had at the time,” he said.

British police records show Boyd reported a break-in, with two laptops stolen from his London apartment in November 2014. Asked by Fox News what was on the computers, Boyd said, “A lot of information and a lot of evidence about corruption and scandals in Venezuela that I’ve been compiling throughout the years.”

After the break-in, Boyd said his sources were attacked. “People that were believed to be collaborating and sending me information from Venezuela were assaulted in Venezuela by the intelligence police of Mr. Chavez,” he said.

Asked if Fusion GPS was tasked with coming after him, Boyd said, “I believe that they were involved in the defamation campaign — smearing campaign — shortly after my apartment was broken into.”

Boyd says he was labeled a pedophile, drug addict and thief on the web. “They published this information through a number of social media and websites anonymously. They created fake Twitter accounts with my name, impersonating myself. ... They started publishing photos of me walking around London with my daughters. They produced a huge amount of information — fake information — about me, accusing me from being a pedophile to being an extortionist to a drug trafficker to a car thief.”

Boyd says he believes three suspects, seen in security camera video released by British police, left pictures of his children inside his coat pocket as a warning. “The message, I believe at the time — we know where you are and we know where your children are, so take that as a threatening message.”

And there was more.

“After about a week,” Boyd explained, “two sets of envelopes were sent to me from Tbilisi, Georgia, containing the same exact same pictures — printout of pictures — that were left in my jacket, but this time the printouts had handwritten messages saying, ‘You touch the wrong girl you pedophile, you think we can’t touch yours?’”

Fusion GPS is led by Glenn Simpson and Peter Fritsch, who left the Wall Street Journal about a decade ago. Boyd provided Fox News with a travel document that Boyd said indicates Fritsch traveled to Venezuela, as part of what he described as an effort to shut down any investigative reporting into Derwick's actions. Asked if Fusion GPS plays on its credentials as former journalists, Boyd said yes.

FUSION BOSS REFUSED TO ANSWER BASIC QUESTIONS ON ANTI-TRUMP DOSSIER, SOURCE SAYS

“I believe that they are basically cashing in on the years of experience they have accumulated collectively in different newspapers, in different media around the world,” he said.

Boyd’s allegations mirror sworn congressional testimony from Bill Browder, an American businessman who told senators this summer that Fusion GPS used smear tactics to discredit him and his late attorney Sergei Magnitsky who, he says, was tortured and murdered eight years ago in a Russian jail. The so-called Magnitsky Act issued tough economic sanctions against Russia which are still in place today.

In the Magnitsky case, Browder filed a complaint with the Justice Department in July 2016 because he says Fusion worked on behalf of a foreign government and its interests. The Justice Department would not comment on the complaint status.

In a congressional declaration, human rights activist Thor Halvorssen also said Fusion GPS had “smear experts” and used “scorched earth methods.”

To date, Simpson has refused to reveal his sources and who paid for the Trump dossier, with Fusion attorney Joshua Levy threatening in an Oct. 16 letter that Simpson and others will take the Fifth if they are required to appear before the House Intelligence Committee.

Defending the company’s work on the Trump dossier, Levy wrote: “Of acute importance, these subpoenas, if indeed directed to our clients, violate the First Amendment rights of our clients and their clients, and would chill any American running for office — regardless of party affiliation, political viewpoint or candidate preference — from conducting confidential opposition research in an election. No individual should be expected to respond to such an abuse of power.”

Boyd was dismissive of Fusion’s First Amendment arguments. “I do not believe that certain privileges that apply to journalists and lawyers should apply to Mr. Simpson because he is neither — he’s a spin doctor.”

Simpson once railed against the kinds of aggressive opposition research tactics that are allegedly the lifeblood of his current company.

Ironically, in a 1996 book that Simpson co-authored with Larry Sabato entitled, “Dirty Little Secrets: The Persistence of Corruption in American Politics,” the authors wrote, “At its worst, opposition research can be a gateway to acts that are not just offensive but duplicitous and sometimes illegal.”

Levy did not respond to multiple requests for comment from Fox News over a two-day period about its work in Venezuela and Boyd’s allegations.

The Metropolitan Police in London confirmed an investigation into Boyd’s apartment break-in, but the case was closed when the leads went cold.

After Fox News emailed Alejandro Betancourt, CEO at Derwick Associates of Venezuela, Florida-based attorney Joseph DeMaria responded but did not address Fox News’ questions about the company’s relationship with Fusion GPS and the Boyd allegations:

“I have represented Derwick and Messrs. Betancourt and Trebbau for the past five years in Florida litigation. Mr. Halvorssen filed a defamation and tortious interference lawsuit against Derwick and Messrs. Trebbau and Betancourt, which I defended successfully. The case was dismissed by the trial court and just last week, the Florida Court of Appeal affirmed the dismissal. Thus, after defeating Mr. Halvorssen’s claims, you can understand why Derwick and its principals have no desire to have any further involvement with Mr. Halvorssen. They did their speaking against Mr. Halvorssen in Court and have no further comment to make regarding Mr. Halvorssen or his allegations.”