Seventy-eight-year-old billionaire financier and investor Thomas H. Lee was reportedly found dead Thursday inside his Manhattan office.

According to law enforcement sources, Lee died of an apparent self-inflicted gunshot wound, the New York Post reported.

When they received an emergency call that morning, officers responded to the 767 Fifth Avenue location where Thomas H. Lee Capital LLC’s office is on the sixth floor.

Emergency crews later pronounced the man dead, and it is now up to the medical examiner to determine an official cause of death.

“Lee is credited with being one of the first financiers to purchase companies with money borrowed against the business being bought — what is now called a leveraged buyout,” the Post report said.

After graduating from Harvard, he founded Thomas H. Lee Partners L.P. in 1974. Years later, he purchased Snapple, but eventually sold it for $1.7 billion, which resulted in him making over 30 times his own funds.

The Post article continued:

In 1999, Lee led a deal for what was renamed Vertis Communications, the fifth-largest North American printer. By 2006, when many peers had expanded to offer other services, such as marketing, it dropped to ninth since it did not have the money to do the same. Vertis filed for bankruptcy in 2008.

Lee and his longtime partners split in 2005, with Thomas H. Lee Partners being run by Scott Sperling, and Lee left to form Lee Equity Partners in 2006, where he served as chairman until his death Thursday.

Lee was first married to Barbara Fish Lee in 1968, and the couple had two children. However, they divorced in 1995, and he married Ann Tenenbaum two years later. The couple had three children together, the Daily Mail reported Thursday.

The outlet added, “Lee was a good friend of Bill and Hillary Clinton and in June 2008, following Hillary’s unsuccessful presidential run, the couple reportedly stayed at his East Hampton home.”

In a statement, spokesman for his family, Michael Sitrick, said, “While the world knew him as one of the pioneers in the private equity business and a successful businessman, we knew him as a devoted husband, father, grandfather, sibling, friend and philanthropist who always put others’ needs before his own.”

Lee’s reported net worth was $2 billion at the time of his death.

His philanthropy was geared towards the arts and education. In 1996, he donated $22 million to his alma mater, Harvard University, the Post report stated.