The presence of far-right conspiracy theorist Laura Loomer alongside Donald Trump during the campaign in recent days has raised questions, including among some Republicans, about the influence the controversial former congressional candidate might have on him.

Ms. Loomer is known for her anti-Muslim rhetoric and for spreading conspiracy theories, including that the September 11 attacks were an “inside job” by the US government.

She attended a memorial service for the attacks with Trump on Wednesday, raising eyebrows and sparking outrage in some American media.

And on Tuesday, the 31-year-old traveled aboard Trump’s plane to Philadelphia for the presidential debate in the city.

Perhaps the most memorable moment of that debate came when Trump repeated an unsubstantiated claim that illegal immigrants from Haiti were eating pets in a small Ohio town. “They’re eating the pets of the people who live there,” he said.

City officials later told BBC Verify that there are “no credible reports” that this actually happened.

Mr Trump said he was repeating claims he had heard on television, but the unsubstantiated theory was aired by Ms Loomer a day before the debate. On Monday, the fringe pundit and social media influencer repeated the unsubstantiated claims to her 1.2 million followers on X.

While it is unclear to what extent Ms. Loomer has access to Trump, and his running mate JD Vance has also spread the unfounded theoryMs. Loomer’s post and her presence in Philadelphia has led some Republicans to blame her for the former president’s unsubstantiated claim onstage.

An anonymous source close to the Trump campaign told the American news outlet Semafor that they were “100%” concerned about Ms. Loomer’s rapprochement with Trump.

“Regardless of the restrictions the Trump campaign has put on her, I don’t think it’s going to work,” the source was quoted as saying.

However, another source told the newspaper that Ms Loomer did not interfere with preparations for the debate and that she was a “positive person to be around”.

Dennis Lennox, a Republican consultant, was much more pointed in his criticism of Trump’s debate performance and Ms. Loomer. “That’s what happens when you just take a chance, live in the Fox News-X bubble and rely on Matt Gaetz, let alone Laura Loomer,” he told Semafor.

Ms Loomer did not respond to several requests for comment from the BBC.

But on X, formerly Twitter, she said she is acting “independently” to help Trump, whom she called “truly our nation’s last hope.”

“To the many reporters who call me and obsessively ask me to talk to them today, the answer is no,” she wrote. “I am very busy with my stories and investigations and do not have time to investigate your conspiracy theories.”

The self-proclaimed investigative journalist was born in Arizona in 1993 and has worked as an activist and commentator for organizations such as Project Veritas and Alex Jones’s Infowars.

In 2020, she ran for the Republican Party in the Florida House of Representatives with Trump’s support, but lost to Democrat Lois Frankel.

She tried again two years later, when she ran unsuccessfully to defeat Rep. Daniel Webster in a Republican primary in another Florida district.

Now she is known for her open support for Trump and for spreading a long list of conspiracy theories, including the claim that Kamala Harris is not black and that the son of billionaire George Soros sent cryptic messages calling for Trump’s assassination.

These posts led to her being banned from a number of platforms, including Facebook, Instagram and even, she says, Uber and Lyft, for making offensive comments about Muslim drivers. She once described herself as a “proud Islamophobe.”

Ms. Loomer regularly attends events in support of Trump and was previously seen at his Mar-a-Lago home in Florida.

Earlier this year, she flew to Iowa on his plane, where he cheered her onstage at an event. “You want her on your side,” Trump said. The former president has also shared several of her videos on Truth Social.

And last year, the new york times reported that Trump had expressed interest in hiring her for his campaign, but only relented after his top advisers expressed concern that she could harm his election campaign.

“Everybody who works for him thinks she’s a burden,” a Trump adviser said of Ms. Loomer in an NBC News report in January.

Another outspoken Trump supporter, Marjorie Taylor Greene, took issue with Ms. Loomer this week over comments questioning Harris’s race and a post saying the White House would “smell like curry” if Harris — who is of part Indian descent — is elected.

Greene called Ms. Loomer’s comments “shocking and extremely racist” and “not representative of who we are as Republicans or MAGA,” prompting a flood of angry messages in her direction.

The feud within Trump’s sphere of influence unfolded just a day after Ms. Loomer attended events with Trump commemorating the 9/11 anniversary in New York and Pennsylvania.

When asked by the Associated Press about her attendance, she said she did not work for the campaign and that she was “invited as a guest.”