Scott M. Bowman, once assigned to the bureau's Los Angeles field office, also admitted to filing false reports and to tampering with a witness in attempt to cover his tracks, according to federal prosecutors.
Bowman, 45, pleaded guilty to the charges before U.S. District Judge Jesus G. Bernal. He is scheduled to be sentenced August 15, according to a Justice Department news release.
Bowman's attorney, James Spertus, said his client accepted full responsibility for his crimes.
"Mr. Bowman has paid a heavy price for his errors in judgment," the lawyer said.
Money came from gang task force probe
Bowman, a 10-year-veteran of the FBI, stole money seized during the execution of search warrants in the summer of 2014 when he worked on a gang task force based in San Bernardino, east of Los Angeles, according to prosecutors.
Following the thefts, Bowman submitted false reports, forged a signature and asked a local police officer assigned to the task force to lie for him if questioned by investigators.
He spent more than $43,000 on a Dodge Challenger, $27,500 on a Scion FRS and another $26,612 to outfit the cars with new speakers, rims and tires. The surgery for his wife cost $15,000, according to prosecutors.
One criminal case dismissed
In the wake of Bowman's arrest, at least one criminal case he worked on as an agent was dismissed. It was not immediately clear what impact, if any, his guilty plea may have on other cases.
James Struyk, acting director in charge of the FBI in Los Angeles, said in a statement that the FBI reported Bowman to the Justice Department's inspector general once learning of his misconduct.
"As Mr. Bowman takes responsibility for his actions by pleading guilty," Struyk said, "the public should be reminded that FBI personnel are held to the highest standards and misconduct of any kind is taken very seriously."