Washington (CNN) Donald Trump's presidential campaign said Sunday it fired a staffer after racially charged Facebook posts he allegedly wrote were uncovered Friday.

Effective immediately, Sam Nunberg, a Trump political adviser, is "no longer associated with the Donald J. Trump for president campaign," Trump campaign manager Corey Lewandowski confirmed to CNN.

The news of Nunberg's firing was initially reported by Mark Halperin of Bloomberg Politics

Nunberg allegedly wrote racially charged and disparaging political posts dating back to 2007, including one calling civil rights leader Rev. Al Sharpton's daughter a "N—!" and another calling President Barack Obama a "Socialist Marxist Islamo Fascist Nazi Appeaser," Business Insider reported Friday . Nunberg is denying he wrote the posts.

Lewandowski told CNN on Friday that the posts are "offensive" and said Nunberg would be fired if he indeed wrote those posts.

"They were offensive and they do not reflect Mr. Trump's position and we take them very seriously," he said. "If it determined that Mr. Nunberg made these statements then he will no longer be part of the campaign."

Lewandowski said he oversees "personnel decisions" as campaign manager and promised a "swift decision" once he can verify whether or not Nunberg authored the posts.

Nunberg denied he wrote the posts and said "anything that was posted under my name does not mean I posted it."

"I am not adept at social media," he told CNN on Friday. "I have a long record of working with diverse people. And anything you are reporting on does not reflect anything on Mr. Trump or Mr. Trump's campaign. I would also point out that all of these things were done before Mr. Trump's campaign, if I even did them — which I deny. In any event, this is the problem with politics ... Politics as usual is wrong."

The controversy comes as Trump's presidential campaign is entering its seventh week -- weeks that have centered on controversial comments by Trump and his aides. Just this week, Trump's special counsel, Michael Cohen, made headlines for stating that a husband can't rape his spouse -- comments he later called "inarticulate."

Nunberg, an associate of political strategist and former Richard Nixon aide Roger Stone, previously advised Trump in 2012, when Trump last considered running for president but ultimately bowed out and endorsed Republican nominee Mitt Romney.

Trump fired Nunberg after he arranged for a Buzzfeed News profile of Trump that ran with the headline "36 Hours on The Fake Campaign Trail with Donald Trump."

He later hired Nunberg again in the run-up to his 2016 presidential bid.

Nunberg's Facebook posts, as reported by Business Insider, also allegedly shows the political aide flinging insults at President Barack Obama.

"thinks that Obama is a Socialist Marxist Islamo Fascist Nazi Appeaser - congrats to the losters that voted for him," Nunberg allegedly posted in 2009.

And, "Rush has called it - Obama is not getting universal Kenyan health care, take it to the bank!"

The posts also include attacks against New Jersey Gov. Chris Christie, calling the Republican a "fat slob" and pointing out that the only think Christie likes "more than lasagna" is himself.