Fox News has retracted a story about Seth Rich, a Democratic National Committee staffer whose unsolved murder had become the focal point of several right-wing conspiracy theories, six days after CNN first pointed out problems with its reporting, and just hours after the brother of the murder victim pleaded with the network to stop prime-time host Sean Hannity from spreading “baseless accusations” about his family.

“On May 16, a story was posted on the Fox News website on the investigation into the 2016 murder of DNC Staffer Seth Rich,” Fox News said in a brief statement. “The article was not initially subjected to the high degree of editorial scrutiny we require for all our reporting. Upon appropriate review, the article was found not to meet those standards and has since been removed.”

Speculation about the reason for Rich’s murder began spreading online within weeks of his July 2016 death, fueled by a $20,000 reward offered by WikiLeaks for information about the case, and later by WikiLeaks founder Julian Assange, who suggested on a Dutch radio show that Rich may have been involved in the D.N.C. hack attributed to Russia. Roger Stone, a longtime confidant of Donald Trump, was among those on the right who insinuated that Rich had been killed by the Clintons in order to cover up the evidence. (Washington, D.C. police have said evidence suggests Rich was the victim of a botched robbery.)

The theory that Rich, not the Russians, might be behind the D.N.C. hack remained confined to Russian propaganda outlets and right-wing fever swamps until May 16, when Fox News aired an interview, and later wrote a story on FoxNews.com, featuring a claim by Rod Wheeler, a Fox News contributor and private investigator working with the Rich family, that Rich had been in contact with WikiLeaks before his death. The news was quickly picked up by Breitbart (“NOT RUSSIA, BUT AN INSIDE JOB?”) and the Drudge Report (“ DEAD DNC STAFFER 'HAD CONTACT' WITH WIKILEAKS”) before the story began to fall apart under scrutiny. Contacted by CNN, Wheeler said he was only previewing information given to him by a Fox News reporter for the network’s own upcoming story, and that he had no evidence of his own. The Fox News producer and editor who worked on both stories did not respond to CNN’s requests for comment.

While nearly every other news network covered reports that Trump had pressured then-F.B.I. director James Comey to drop his investigation into Mike Flynn, Fox News spent days fixated on the debunked Seth Rich story, despite pleas by the Rich family to stop spreading conspiracy theories. Sean Hannity was the network’s biggest on-air proponent of the story, repeatedly raising questions about the case and suggesting that a Rich-WikiLeaks connection could prove allegations of Russian election meddling were fake. Even after a spokesman for the Rich family condemned the reporting as an attempt to “manipulate the legacy of a murder victim in order to forward their own political agenda,” Hannity soldiered on, asking, “Does that sound like a robbery to you? Because it doesn’t sound at all like a robbery to me.”

Hannity’s colleagues at the network were reportedly “disgusted” that News Corp had not done enough to disavow the story. “ARE WE STILL AIRING THAT SHIT?!” one Fox political reporter vented in a message to The Daily Beast. Their anonymous complaints, however, fell on deaf ears.

On Tuesday, the brother of the slain D.N.C. staffer issued an emotional statement calling on Hannity, again, to stop spreading misinformation about his death. “Nobody wants to solve Seth’s murder more than we do,” Aaron Rich said. “However, providing a platform to spread potentially false, damaging information will cause us additional pain, suffering and sorrow.”

Hours later, Fox News released a statement saying that the Seth Rich story “was not initially subjected to the high degree of editorial scrutiny we require for all our reporting,” and had been removed. The network added that it would “continue to investigate this story.” The statement did not address Aaron Rich’s claim that Hannity had invited Kim Dotcom, an infamous hacker who claimed to have information on Rich’s murder, to be on the show Tuesday night. (A spokesperson for Fox News declined to comment.)

Hannity, meanwhile, appeared undeterred by Fox News disavowing its earlier reporting on Rich. Shortly after Fox released the retraction, Hannity published two tweets highlighting a statement from Dotcom, who has been indicted by U.S. authorities on multiple charges and is currently fighting extradition in New Zealand. “Read Kim Dotcom and listen to the Democrats say over and over NO EVIDENCE OF COLLUSION,” he wrote. Later Tuesday, on his radio show, Hannity doubled down again. “I am not FoxNews.com. I retracted nothing!”

Later that night, Hannity seemed somewhat chastened, explaining during his show that he would temporarily stop covering the Seth Rich story “out of respect for the family’s wishes.” That said, he hinted at his continued fixation. “There are so many issues here, not the least of which is the Democratic push of their Russia narrative,” he said, before repeating his assertion that the “‘destroy-Trump media’” was up to something sinister. “They have been pushing the Russian tinfoil-hat conspiracy story with zero evidence,” he added, without a hint of irony.