http://news.yahoo.com/s/ap/20091231/ap_on_go_ot/us_cia_afghan_attack

WASHINGTON – The CIA said Thursday that seven of its employees were killed and six others wounded in a suicide bombing at a base in Afghanistan. The Associated Press has learned that one of them was the chief of the CIA's post in Afghanistan's southeastern Khost Province.

CIA Director Leon Panetta said in a message to agency staff that the casualties sustained in Wednesday's strike at Forward Operating Base Chapman were the result of a terrorist attack. The Taliban claimed responsibility for the bombing.

Initial reports indicated that eight American civilians had been killed. There was no explanation for the discrepancy in Panetta's message, which was released by the CIA in an unusual step a day after one of the deadliest attacks on the agency in its history.

"Those who fell yesterday were far from home and close to the enemy, doing the hard work that must be done to protect our country from terrorism," Panetta said. "We owe them our deepest gratitude, and we pledge to them and their families that we will never cease fighting for the cause to which they dedicated their lives — a safer America."

"Yesterday's tragedy reminds us that the men and women of the CIA put their lives at risk every day to protect this nation," he said. "Throughout our history, the reality is that those who make a real difference often face real danger."

No further information about the victims would be released, the CIA director said, "due to the sensitivity of their mission and other ongoing operations."

Separately, former CIA officials said an agent who ran the agency's base in Khost was among those killed by the attacker, who detonated a bomb-laden vest inside the compound.

The former officials said the Khost chief was the mother of three.

As base chief she would have directed and coordinated CIA operations and intelligence gathering in the province, a hotbed of Taliban and insurgent activity because of its proximity to Pakistan's lawless tribal region, they said.

The former officials spoke on condition of anonymity because they were not authorized to speak publicly.

It was not immediately clear how the bomber entered the base at the edge of Khost city and was able to circumvent security. Khost is the capital of Khost province, which borders Pakistan and is a Taliban stronghold.

"Theres still a lot to be learned about what happened," CIA spokesman George Little said. "The key lesson is that counterterrorism work is dangerous."

Taliban spokesman Zabiullah Mujahid said in a statement that an Afghan National Army officer wearing a suicide vest entered the base and blew himself up inside the gym. A U.S. official briefed on the blast also said it took place in the gym.

Forward Operating Base Chapman used to be a military facility base but was later turned into a CIA base, according to a U.S. official, who spoke on condition of anonymity because he was not authorized to speak publicly.

Some military men and women work there on a Provincial Reconstruction Team, one of several civilian-military units that secure and develop areas of Afghanistan. A NATO spokesman said other personnel operate from Chapman as well, but he said he could not elaborate.

Wednesday's attack was the single deadliest for Americans in Afghanistan since eight soldiers were killed in an insurgent attack on a base in the east on Oct. 3.

Only four known CIA operatives have been killed in Afghanistan since the Sept. 11, 2001, terrorist attacks in the U.S.

CIA officer Micheal "Mike" Spann was killed in a prison uprising in November 2001. An agency officer died in a training exercise in 2003, and two contractors operating out of a CIA base in Shkin district of Paktika province were killed the same year.