NEW YORK — Berkshire Hathaway Inc. was sued by an ex-manager of its recreational-vehicle business who said he was fired after bringing allegations of “millions of dollars” of fraud to executives including Chairman Warren Buffett.

Brad Mart said in an April 5 complaint that Buffett “took no action to correct the deficiencies” at the RV maker, including the removal of cash from factory vending machines for deposit in a personal account of Forest River Chief Executive Officer Peter Liegl. A representative for Berkshire said Mart never told Buffett, in three conversations, about the behavior, and that a probe found no illegal activity.

Mart is seeking the Forest River CEO post, which he said he was promised, according to the complaint in federal court in South Bend, Ind. He also asked for damages including reimbursement for his loss on the sale of his home in Illinois when he purchased a new property in anticipation of getting the promotion. He accused Elkhart, Ind.-based Forest River of breach of contract and said Liegl threatened his life.

“Because Mart followed the Berkshire Hathaway Code of Business Conduct and Ethics and reported known or suspected violations of the Code by Liegl and Forest River to Warren Buffett, Mart lost his job,” according to the complaint. Liegl “fared much better, retaining his position as CEO of Forest River and keeping the millions of dollars he bilked.”

Mart was fired early last year after helping to arrange Berkshire’s 2005 deal to buy Forest River for about $800 million according to the complaint. Mart said that he was named general manager of the company’s financing business after it was bought by Berkshire and then told in 2007 he would succeed Liegl as CEO.

“Mr. Mart did not alert Mr. Buffett to any unethical, fraudulent or illegal activities” at Forest River, said Berkshire Secretary Forrest Krutter on Thursday. Krutter said Buffett asked him to conduct a review of RV maker related to “business items.” “In the course of the investigation, these allegations came to light,” Krutter said of the fraud claims. “My investigation did not identify any fraudulent, unethical or illegal activities.” Krutter said he’s seen “no evidence or indication” that the allegations of death threats are valid, and that the reasons for Mart’s dismissal aren’t related to his claims.”