A former Donald Trump campaign staffer says in response to a Trump lawsuit against him that the campaign may have broken laws against mingling corporate and campaign funds.

Sam Nunberg, in a legal answer to a $10 million lawsuit claiming Nunberg violated a confidentiality agreement, said Trump may have illegally funneled corporate money into the campaign, and created a fictitious company that was listed as a plaintiff in the lawsuit.

Nunberg was fired from Trump’s presidential campaign last summer, after it was revealed that he had posted racist messages on Facebook. Trump’s lawsuit against him, made public on Wednesday, claims Nunberg in May told the New York Post about a public screaming match between two top Trump staffers: campaign spokeswoman Hope Hicks, and Trump’s then-campaign manager, Corey Lewandowski. Nunberg vehemently denies leaking the story.

Samuel Nunberg

At the time of the argument between Hicks and Lewandowski, Nunberg hadn’t been involved with Trump’s campaign for more than 10 months.

Nunberg says in his answer to the lawsuit that the Trump campaign illegally created a fictitious company, called Trump 2012 PCA. The company is listed as a plaintiff in the suit against Nunberg, along with Trump’s formal campaign.

Samuel Nunberg

Nunberg also claims the campaign “may very well” have violated campaign finance laws by using Trump company resources for Trump’s political campaign.

Samuel Nunberg

News of the lawsuit and response upstaged Trump’s search for a running mate, according to a source close to the campaign, who spoke on the condition of anonymity.

“This is happening on the worst possible day for him,” said the adviser, who added that Trump disregarded advice not to file the lawsuit in the first place.

At the time the lawsuit was filed in May, Trump was relying on Corey Lewandowski, his campaign manager who was subsequently fired. Lewandowski advocated the suit as a way to make sure his relationship with Hicks ― which Nunberg’s filing calls a “sordid and apparently illicit affair” ― didn’t become public, the adviser said.

“Corey egged him on this suit,” the adviser said, adding that once it was filed, Trump was not interested in dropping it. “Trump never backs down.”

“Nunberg will go for Trump’s throat. This is going to be all-out war,” the adviser predicted. “This is going to be ugly.”

Indeed, there were already signs on Wednesday that Nunberg plans to make the legal battle about Trump’s presidential campaign. Nunberg contends his endorsement of Texas Sen. Ted Cruz (R), Trump’s former rival for the Republican nomination, sparked the lawsuit.

Samuel Nunberg

A spokeswoman for the Trump campaign did not respond to a request for comment from The Huffington Post.

Editor’s note: Donald Trump regularly incites political violence and is a serial liar, rampant xenophobe, racist, misogynist and birther who has repeatedly pledged to ban all Muslims ― 1.6 billion members of an entire religion ― from entering the U.S.