Former special counsel Robert Mueller said Wednesday he believes a controversial news report published before the 2016 election that alleged secret contacts between email servers for the Trump Organization and a Russian bank is inaccurate.

The story in question, which was published by Slate, has been a source of much debate since it was published on Oct. 31, 2016. It alleged that a Russian bank called Alfa Bank had a secret line of communication with President Donald Trump’s real estate company, the Trump Organization, possibly for the purposes of collusion.

A lawyer for the Democratic National Committee (DNC) and the Clinton campaign provided information about the alleged server connection in September 2016 to Franklin Foer, the Slate reporter who published the report. Michael Sussmann, the lawyer, also shared information with The New York Times and the FBI’s general counsel.

After the election, a former Senate intelligence investigator who worked with opposition research firm Fusion GPS and dossier author Christopher Steele investigated the same information.

But the story and underlying allegations are wrong, Mueller testified Wednesday before the House Intelligence Committee.

“On October 31st, 2016, Slate published a report suggesting that a server at Trump Tower was secretly communicating with Russia’s Alfa Bank. And I quote, akin to what criminal syndicates do. Do you know if that story is true?” Texas Rep. Will Hurd, a Republican, asked Mueller.

After crosstalk with Hurd, Mueller said that he did not believe the Slate story to be accurate.

“Because I don’t believe it’s not true doesn’t mean I would not have investigated it. It may have been investigated, although my belief at this point: it’s not true,” said Mueller, who struggled at times through more than six hours of testimony before the House Judiciary and House Intelligence Committees.

Some cyber security experts immediately dismissed Foer’s report. But it remained one of the many collusion conspiracy theories that have loomed over the Trump administration for two years. The New Yorker published a story in October breathing new life into the original Slate report.

Mueller’s testimony deals a blow not just to Slate, but to Sussmann, who is a partner at Perkins Coie, the law firm that hired Fusion GPS on behalf of the Clinton campaign and DNC.

According to a report published by Republicans on the House Intelligence Committee on April 27, 2018, Sussmann shared information about the alleged Alfa Bank-Trump Organization connection with Foer.

Sussmann also passed Alfa Bank information to James Baker, who served as the FBI’s general counsel during the early stages of the Russia probe, and to reporters at The New York Times.

The Perkins Coie lawyer met separately with Foer and Baker in September 2016.

Baker told Congress on Oct. 3 that the meeting with Sussmann was the only one he could recall in which an attorney had provided him evidence for an investigation. He acknowledged that the meeting was “abnormal” and “unusual.”

The date of the Baker-Sussmann meeting — Sept. 19, 2016 — was the same day that the FBI’s core Russia investigation team received memos from Steele’s dossier. Baker said that Sussmann did not provide him information from the dossier during their meeting.

Baker said that he had a longstanding personal relationship with Sussmann from their days working together at the Justice Department. He also testified that he did not know why Sussmann picked him as a conduit for the information, but acknowledged that having the FBI’s top lawyer share documents internally at the bureau would give them a certain air of legitimacy.

Baker testified that he immediately gave Sussmann’s files to the FBI’s counterintelligence division, which was investigating possible links between the Trump campaign and Russian government. Mueller’s investigation found no evidence of a conspiracy between Trump associates and the Kremlin. His report did not mention the Alfa Bank allegations.

Baker said that Sussmann relayed that he received the Alfa Bank information from a team of cyber experts who wanted to get it in the hands of the FBI.

The New Yorker reported that Daniel Jones, a former Senate Intelligence Committee staffer who worked with Fusion GPS and Steele, compiled a team of cyber security experts to investigate the Alfa-Trump connection. It is unclear whether Fusion GPS or Steele also investigated the Alfa Bank servers. But Steele’s dossier does include one memo that alleges Alfa’s Russian founders had compromising information on Russian President Vladimir Putin.

Jones, who operates two non-profits, The Democracy Integrity Project and Advance Democracy Inc., told TIME on May 21 that he believed information in the special counsel’s report raised intriguing questions about the Alfa-Trump link.

“Who knows what they were doing with the Alfa server but this new evidence certainly raises all sorts of additional questions,” Jones told TIME.

Baker said that Sussmann told him either in their initial meeting or a follow-up conversation that he had also provided information to The New York Times. The newspaper published a story, also on Oct. 31, 2016, that said the FBI was unable to find evidence of a covert communications channel between the computer servers.

The Times story reached a far different conclusion than Foer at Slate, saying that the FBI investigated the information and did not find evidence of nefarious connections. The newspaper also reported that intelligence officials presented the information to congressional leaders.