A billionaire financier, considered a pioneer of private equity investment, has been found dead in his New York office after reportedly taking his own life.

While the family of Thomas (Tom) H Lee, who was 78, confirmed he had passed away there was yet to be any official confirmation from the New York Police Department (NYPD) on his identity or cause of death.

The New York Post, however, said that police sources had told the newspaper that he was discovered dead in his office at the headquarters of his investment firm Lee Equity on Thursday morning.

The sources gave the cause of death as a "self-inflicted gunshot wound", the paper added.

No indications of ill health or financial trouble were reported by US media while police gave no indication that a murder inquiry was underway.

In its official response, the NYPD said the city medical examiner's office would determine the cause and manner of death.

Relatives said in a statement: "The family is extremely saddened by Tom's death.

"Our hearts are broken. We ask that our privacy be respected and that we be allowed to grieve."

He was considered a pioneer of leveraged buyouts - the purchase of another company using a significant amount of borrowed money to meet the cost of acquisition.

Mr Lee started Lee Equity in 2006 having previously served as chairman and CEO of Thomas H. Lee Partners, which he founded in 1974.

The family said he was responsible for investing more than $15bn (£12.5bn) of capital in hundreds of transactions, including the acquisition and subsequent sales of brand names including Snapple Beverages and Warner Music.

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