A former CIA operative was sentenced to five years in prison Friday for trying to extort $1 million from the agency in exchange for his silence about government eavesdropping operations.

Douglas Fred Groat, 51, pleaded guilty to the extortion charge in July. As part of the plea agreement, federal prosecutors dropped four counts of espionage, including charges that Groat told two foreign governments the CIA had cracked their coded communications.U.S. District Judge Thomas F. Hogan said Groat's actions appeared to stem from his "almost becoming obsessed" about a job dispute with the CIA.

"I don't think at any time you really had any intention of trying to harm our national security," Hogan said.

The judge said he would recommend housing Groat in a minimum-security prison and ordered him to serve three years of supervised release after completing his sentence. He has been held without bail since his arrest in April.

Groat, a burly, bearded man, is the third current or former CIA employee arrested on espionage charges in the past four years. He will be able to collect his CIA pension when he turns 62.