Elon Musk's Grokipedia carries thousands of citations to "questionable" and "problematic" sources, US researchers said Friday, raising doubts about the reliability of the AI-powered encyclopedia as an information tool.

Musk's company xAI launched Grokipedia last month to compete with Wikipedia -- a crowdsourced information repository authored by humans that the billionaire and others on the American right have repeatedly accused of ideological bias.

"It is clear that sourcing guardrails have largely been lifted on Grokipedia," Cornell Tech researchers Harold Triedman and Alexios Mantzarlis wrote in a report seen by AFP.

"This results in the inclusion of questionable sources, and an overall higher prevalence of potentially problematic sources."

The study, which scraped hundreds of thousands of Grokipedia articles, said the trend was particularly notable in topics pertaining to elected officials and controversial political topics.

Grokipedia's entry for "Clinton body count" -- a widely debunked conspiracy theory that links the deaths of multiple people to former president Bill Clinton and his wife Hillary -- cites InfoWars, a far-right website notorious for peddling misinformation.

Other Grokipedia articles cite American and Indian right-wing media outlets, Chinese and Iranian state media, anti-immigration, antisemitic or anti-Muslim sites, and portals accused of promoting pseudoscience and conspiracy theories, the report said.

"Grokipedia cites these sources without qualifying their reliability," it said.

The study found that Grokipedia articles often "contain exactly identical copies of text" from Wikipedia, a site it has intended to outshine.

It said Grokipedia articles not attributed to Wikipedia are 3.2 times more likely than those on the rival platform to cite sources deemed "generally unreliable" by the English Wikipedia community.

They are also 13 times more likely to include a "blacklisted" source which is blocked by Wikipedia, it added.

- 'Trustworthiness' -

AFP's request to xAI for comment generated this auto response: "Legacy Media Lies."

Musk -- the world's richest person and owner of social media platform X who poured hundreds of millions of dollars into US President Donald Trump's election campaign -- has said that Grokipedia's goal is "the truth, the whole truth and nothing but the truth."

On Thursday, Musk said he plans to rebrand Grokipedia as "Encyclopedia Galactica" when it is "good enough (long way to go)."

"Join @xAI to help build the sci-fi version of the Library of Alexandria!" Musk wrote on X.

Musk and the US Republican Party have frequently accused Wikipedia of being biased against right-wing ideas. Last year, Musk urged his more than 200 million followers on X to stop donating to Wikipedia, dubbing the site "Wokepedia."

In a recent interview with the BBC Science Focus podcast, Wikipedia founder Jimmy Wales rejected claims it has a left-wing bias as "factually incorrect," while acknowledging there were areas for improvement among its volunteer community.

"Unlike Grokipedia, which relies on rapid AI-generated content with limited transparency and oversight, Wikipedia's processes are open to public review and rigorously document the sources behind every article," Selena Deckelmann, chief product and technology officer at the Wikimedia Foundation, told AFP.

"It is precisely this deliberate openness and community model that upholds the neutrality and trustworthiness essential for a global encyclopedia: no single individual, company, or agenda can exert influence over the work."