Mary Ann Jennings, director of public information for the Fairfax County, Va., Police Department, said Kellermann was found dead in his suburban Virginia home. The police would not say if a suicide note was found.
Kellermann, 41, lived in Hunter Mill Estates, a well-off neighborhood of large single-family homes with manicured lawns. County records show Kellermann's home is worth about $900,000.
He worked for Freddie Mac for the past 16 years and was named acting chief financial officer last September when the government seized control of the company to keep it from failing. Freddie Mac lost more than $50 billion last year, and the government has pumped in $45 billion to keep the company afloat.
Freddie Mac, which owns or guarantees about 13 million mortgages, has been criticized for financing risky mortgage loans that fueled the real estate bubble.
News of Kellermann's death came as a shock to employees of the McLean, Va.-based company, with those who knew Kellermann tearing up on Wednesday morning and a quiet mood prevailing.