WASHINGTON (CN) – Aaron Rich, the brother of Seth Rich, the former Democratic National Committee staffer shot in the back while walking home in the nation’s capitol two years ago, sued a handful of media outlets on Monday for slandering him.

Seth Rich’s July 2016 murder is still unsolved but authorities’ have said the killing was likely the result of a botched robbery attempt.

The conspiracy theories have continued to persist, nonetheless.

The predominant so-called theory is that Rich was killed in retribution for secretly collaborating with Wikileaks by providing thousands of DNC emails to Wikileaks founder Julian Assange.

It was given currency when Fox News published a report in May 2017 suggesting private investigator Rod Wheeler found evidence connecting Seth Rich to Wikileaks before his murder.

Wheeler later admitted he had no evidence to support his claims, eventually saying his report was based on unverified information provided to him by a source inside Fox news.

Fox eventually issued a retraction and removed the story from its site but the report had already circulated online for six days.

Rich’s parents, Joel and Mary Rich, sued Fox in federal court in New York on March 13, claiming Fox, Fox reporter Malia Zimmerman and Texas-based financial adviser and part-time Fox pundit Ed Butowsky, cooked up the conspiracies about Rich in order to further their own political agendas.

In an entirely separate suit filed Monday, Seth Rich’s brother, Aaron Rich, has named Edward Butowsky a defendant again.

This time, Butowsky is joined by c0-defendant Matthew Couch, owner of America First Media.

That company, as well as the Washington Times, another conservative-leaning outlet; are also named in the 60-page complaint.

According to Rich, Couch, Butowsky and the outlets have defamed him by claiming that he helped his deceased brother steal data from the Democratic National Committee in exchange for hefty payoffs.

Aaron, who describes himself in the complaint as an “intensely private person,” acknowledges that where the “constitutional system leaves wide room for debate on issues of public concern,” the defendants have falsely claimed that they “have proof” suggesting Aaron not only collaborated with his brother and Wikileaks, but that he “engaged in deceit and obstruction of justice to cover his tracks after Seth was murdered.”

“Defendants are not interested in the truth … [they] are motivated by personal notoriety, financial gain and naked partisan aims – namely, a desire to discredit allegations that the Trump campaign colluded with the Russian government in the 2016 hack of the DNC and the subsequent dissemination of DNC documents on Wikileaks.”

In their blind pursuit, Aaron Rich contends, they have “willfully trampled” on his reputation and emotional wellbeing.

To support his defamation claims, Rich points to tweets allegedly made by Couch online in September 2017.

“Seth Rich and Aaron rich did the leak together, they were working together. When is Aaron Rich going to come clean for his brother,” defendant Couch is alleged to have written on Twitter.

That tweet and others appear in a collection of exhibits included with the complaint.

Aaron Rich claims he attempted to talk privately with Couch and Butowsky, asking them to stop spreading the false allegations.

“[Aaron] asked them to consider how they would feel to be accused of complicity in their own brother’s murder,” the complaint states.

But after receiving those letters, the defendants “doubled down and then tripled down on their behavior, [continuing] to disseminate false statements about Aaron and then upped the ante by conspiring to have their lies about Aaron published in a prominent national newspaper,” the complaint says.

Couch allegedly continued to slander Rich.

In December, Couch allegedly posted a photo on Twitter showing the brothers embracing at a wedding.

In his tweet, Couch allegedly wrote: “The apple doesn’t fall far from the tree… Aaron Rich took money into his personal account from Wikileaks. #SethRich #AaronRich #AmericaFirstMedia #HisNameWasSethRich.”

Rich is represented by D.C.-attorney Michael Gottlieb of Boies Schiller Flexner.

Representatives for the defendants did not immediately respond to request for comment but on Twitter, Tuesday afternoon, Couch fired off a series of tweets about the new defamation suit.

“So apparently, according to the lawsuit filed against our team and others, Aaron Rich already testified in front of a secret grand jury that’s sole purpose is Seth Rich’s murder … sounds like some folks in D.C. have some more explaining to do,” Couch allegedly tweeted.

According to the complaint, Aaron Rich has merely “followed up regularly with the officials regarding their investigation and voluntarily testified under oath as a witness before a grand jury convened to investigate Seth’s murder.”