Some big names in media and politics are demanding to know: Why won't anyone thoroughly investigate the mysterious murder of Democratic National Committee staffer Seth Rich and its possible connection to DNC emails leaked to WikiLeaks during the 2016 presidential campaign?

"He's been killed, and apparently nothing serious has been done to investigate his murder," said former U.S. House Speaker Newt Gingrich, calling the murder case a "very strange story" and linking it to DNC emails released to WikiLeaks.

Other pundits chimed in, including talk-radio hosts Rush Limbaugh, Laura Ingraham and Herman Cain, as well as activist and blogger Pamela Geller and Fox Business Network anchor Lou Dobbs.

Meanwhile, Fox News issued a bombshell retraction Tuesday, disavowing a story it posted on May 16 about the Rich murder case that set off a flurry of other reports by conservative news sites. Fox stated in its retraction:

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"On May 16, a story was posted on the Fox News website on the investigation into the 2016 murder of DNC Staffer Seth Rich. 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. We will continue to investigate this story and will provide updates as warranted."

Fox 5 DC, which originally broke the story on May 16, did not retract its story but did run a "clarification" on May 17 telling readers that its main source, private investigator Rod Wheeler, had "since backtracked" on what he originally told the Fox affiliate and had refused to return the station's calls and emails.

Also, the liberal media watchdog Media Matters for America is now pressuring advertisers to pull ads from the Sean Hannity's Fox News show unless Hannity also agrees to bury the story. Media Matters on Tuesday published a list of Hannity's advertisers — a long list that includes major companies such as Allstate, Angie's List, Bayer, Capitol One, Hewlett Packard Enterprise, Mercedes-Benz and Publishers Clearing House.

But Hannity stood by his coverage of the story.

"I am not Fox.com or FoxNews.com, I retracted nothing," Hannity said on his nationally syndicated radio program Tuesday.

Hannity ripped his critics and the mainstream media, saying, "For those accusing me of pushing a conspiracy theory, you are the biggest phony hypocrites in the entire world.

"This issue, it's so big now that the entire Russia collusion narrative is hanging by a thread," he said, referencing media coverage of the investigations into the Trump campaign and possible ties to Russia's meddling in the presidential election last year.

"If in fact, take Seth out of it, there was a whistleblower within the DNC — a truth-teller that was actually the source for WikiLeaks, not Russia — working with the Trump campaign. These are questions that I have a moral obligation to ask, and I will do the mainstream media's job like I have most of my career."

The family of Seth Rich wrote a letter to Hannity's executive producer urging the prime-time program to stop pushing the "conspiracy theory."

“Think about how you would feel losing a son or brother. And while dealing with this, you had baseless accusations of your lost family member being part of a vast conspiracy," Aaron Rich wrote in the letter, which was provided to CNN.

"As the family, we would hope to be the first people to learn about any such evidence and reasons for Seth's death," Rich continued. "It is a travesty that you would prompt false conspiracy theories and other people's agendas rather than work with the family to learn the truth."

The Rich family thanked Fox for the retraction: "The family would like to thank Fox News for their retraction on a story that has caused deep pain and anguish to the family and has done harm to Seth Rich's legacy," a family spokesman told CNN.

On his Fox News' show Tuesday evening, Hannity addressed his audience, saying:

I totally and completely understand how upset, how hard this is on this family, especially over the recent coverage of Seth's death. I've been communicating with them. I got a very heartfelt note and also sent them a heartfelt note back. I reached out personally today to Seth's brother, Aaron. I expressed my condolences over how hard, how difficult this has been for him and his family. As I told Aaron, my heart, my soul, my prayers, everything goes out to them in this very difficult time. I'm a father. I know, I personally don't think I'd ever recover from losing a child or a brother. I honestly don't think I would. I cannot imagine the pain that they are in. And as a father, when I saw the video of the parents online saying they want answers – and I know the brother, Aaron, started a GoFundMe page – it truly pained me. However, out of respect for the family's wishes for now, I am not discussing this matter at this time.

Later in the same segment, Hannity added: "I promise you I am not going to stop doing my job to the extent of my ability. I am not going to stop trying to find the truth. That's what we do here every single day. That effort is not stopping in any way, shape, matter or form. I am continuing the work that I promised to do every day for you. And at the proper time, we shall continue and talk a lot more."

After his Fox show was over Tuesday night, Hannity told WND by email, "I back down from NOTHING and I'm closer than ever."

The entire weight of the establishment news media came down Monday upon Newt Gingrich because Gingrich sounded off on Fox News Sunday about a lack of coverage of the Rich story. The New York Times, New York Daily News, Washington Post, Salon, Daily Mail, USA Today, CNN, CNN Money, Newsweek, Media Matters, Washington Examiner, the Guardian, the Daily Caller and Think Progress all ran stories attacking Gingrich and Hannity for spreading "conspiracy theories" about Rich's murder.

Foreign Policy magazine posted a story Sunday saying the Seth Rich story initially broken by Fox on May 16 shows that Fox News "is morally bankrupt."

CNN Money's story and headline appeared to be written more like an editorial than a news story under the headline "Fox News removes Seth Rich story 6 days after it was debunked" and accused Fox of not using standards eerily similar to those used for its own stories linking President Donald Trump to Russia's alleged influencing of the 2016 presidential election.

The following is a list of what other prominent media pundits have been saying about Seth Rich:

Newt Gingrich: "At the same time, we have this very strange story now of this young man who worked for the Democratic National Committee who apparently was assassinated at 4 in the morning, having given WikiLeaks something like 23,000 – I'm sorry 53,000 emails – and 17,000 attachments. Nobody is investigating that. And what does that tell you about what was going on? Because it turns out, it wasn't the Russians. It was this young guy who, I suspect, was disgusted by the corruption of the Democratic National Committee. He's been killed, and apparently nothing serious has been done to investigate his murder. So I'd like to see how Mueller is going to define what his assignment is, and if it is only narrowly Trump, the country will not learn what it needs to learn about foreign involvement in American politics."

Rush Limbaugh: "Seth Rich, he was murdered, DNC worker. The police said it was a botched robbery. He still had his wallet, car keys, lottery tickets, whatever else. Others are claiming that he was murdered because he was the leak from the DNC to WikiLeaks. And this story is now starting to get legs, that Seth Rich was murdered, it was a contract hire killing because he was leaking to WikiLeaks, he was the one. May have been a Bernie supporter. The only colluding and rigging here, folks, is the Democrat primary election. The DNC rigged it against — do you know that there’s a class-action lawsuit against the DNC over this now? There is a massive lawsuit against the DNC by Bernie supporters for him getting shafted. Seth Rich claims to have been — or there are people claiming. Kim Dotcom, the noted hacker, has now come forward and said he was working with Seth Rich to get the documents to WikiLeaks."

Laura Ingraham, a radio host and Fox News contributor, appeared on Fox and Friends on May 16 and said it was "bizarre" that D.C. police have insisted that Rich's murder was a robbery gone bad when there appears to be no evidence to suggest that. She asked Fox "wheres the follow up?"

Ingraham posted this on her own website: "The murder of Seth Rich has taken a strange twist after a private investigator working for the Rich family claiming that the slain DNC staffer may have leaked the organization’s emails to WikiLeaks — a charge that WikiLeaks founder Julian Assange appears to be endorsing. Rich was shot to death in Washington, D.C., last summer in a case that remains unsolved. While police said that his murder was a robbery gone wrong in a neighborhood that had seen a spate of armed robberies, some conspiracy theorists believed that the young Democratic National Committee employee was really killed in retribution for leaking the organization’s emails to WikiLeaks. The organization published them over the course of the 2016 presidential campaign, which turned out to be politically damaging to Hillary Clinton."

Author/blogger/activist Pamela Geller: "The despotic Democrats are killing people, literally, while waging a relentless campaign of disinformation and false accusations against President Trump — throwing up every roadblock to stop him from enacting policies he campaigned on, and the American people elected him for. Imagine if we had done this to that traitor Obama.

"The Democrats would have waged a bloody civil war just as they did against freeing the slaves. And they are waging the same kind of civil war now (also a war against freedom). This, too, will get bloody. How long are we going to put up with this?

"We thought it would be better under Trump. On the contrary, the left, complacent about the right under Obama, has sprung into action. Facebook and Twitter, the arena of open ideas and organic communication, has been shut down to us. Our content blocked, our timelines shadow-banned. Universities are in leftist lockdown. Trump supporters are ridiculed, demonized even attacked.

"Whoever President Trump picks to head up the FBI, the murder of Seth Rich must be a priority. The party of destruction and murder must be put down."

Herman Cain, a former GOP presidential candidate and radio host in Atlanta, blogged about the Rich story, saying there are plenty of unanswered questions that should be investigated but don't hold your breath that the media will ever push for those answers:

Fox's "former federal investigator" is still anonymous. Given the amount of bogus anonymously sourced stories we've endured lately - both pro and anti-Trump - skepticism is warranted. We have no way of knowing if these sources are unimpeachable. If there really is some kind of global conspiracy here, who's to say these people are on the up and up? It's just as possible that they're compromised by "the Russians" as anyone else. Until we see the contents of that laptop - assuming it hasn't been smashed - we may never know the truth.

"Assuming all the above is true," Cain continued, "it would implicate some of the United States' most powerful Democrats in the murder of a young man who was, by all accounts, a genuine patriot with a promising future. Is it possible that the intel community is trying to destroy the current administration to keep this cover-up alive and protect those responsible?

"Also, is it possible that Comey's bizarre protection of Hillary Clinton, and subsequent bizarre re-opening announcement, could have represented the actions of a man who didn't want to throw the election to Trump, but later decided he couldn't live with the conspiracy?

"As I said before, all of this should be taken with a huge grain of salt. Until we know more, and until someone is willing to put their name to the accusation, it's all speculation. We'll have to wait and see if there's any fire beneath the smoke."

Author and investigative reporter Diana West has published an entire series on Seth Rich.

WikiLeaks founder Julian Assange himself has commented on the Rich murder and suggested that he was a source for his WikiLeaks revelations about the DNC.

"I am suggesting our sources take risks and they become concerned ... we have to understand how high the stakes are in the United States. Our sources take considerable risks. That's why they come to us, to get anonymity.

"We are investigating to understand what happened in that situation with Seth Rich. I think it is a concerning situation … there is not a conclusion yet. We would not be willing to state a conclusion, but we are concerned about it. More importantly, A variety of WikiLeaks sources are concerned when that kind of thing happens."

Lou Dobbs, in an interview with Republican strategist Ed Rollins on the Fox Business Network, said there was "a partisan shroud" around the family of Seth Rich, indicating a full-blown cover up was in progress. Here is a transcript of that interview: