Less than a month after suggesting that terrorist leader Usama bin Laden is dead, the head of the FBI's counter-terrorism department announced Thursday that he will retire next month.

Dale Watson took over the FBI's counter-terrorism office in 1999, when the division was created, and was elevated to executive assistant director of the agency last December, where he was in charge of crime and cybersecurity. He will be succeeded by Bruce J. Gebhardt, currently second-in-command. Gebhardt will directly oversee all FBI investigative, counterintelligence and prevention efforts.

FBI Director Robert S. Mueller called Watson "a visionary, leading change in the FBI at a critical moment in our history" and credited him with helping improve relations with the CIA.

"Dale Watson has served the FBI and the American public with distinction for more than 24 years," Mueller said.

Colleagues said that at 52 years old, Watson is eligible for retirement and had been discussing it prior to his controversial speech last month.

In July, Watson shocked the Bush administration with his candid response to a question on whether he thought bin Laden is still alive.

"I personally think he is probably not with us anymore but I have no evidence to support that," Watson said.

Watson was the point man on the U.S. Embassy bombings in Kenya and Tanzania, the attack on the USS Cole in Yemen and the Khobar Towers attack in Saudi Arabia.

In the last month, a half-dozen top FBI officials have announced their departure from the bureau, an indication of the turnover of personnel that accompanies administration changes rather than frustration with FBI intelligence activities.

Watson is joining the Washington-based consulting firm of Booz Allen Hamilton.

Fox News' Carl Cameron and the Associated Press contributed to this report.