NBC News reported that a former CIA official identified the bomber as Humam Khalil Abu-Mulal al-Balawi, a 36-year-old doctor from the Jordanian town of Zarqa. That town has been notorious for the militants it has spawned, the most infamous being Abu Musab al Zarqawi who led attacks against Americans and Shiite Muslims in Iraq that were bloody, even by that war's standards. He was killed by American troops in 2006.
The Associated Press reported that al-Balawi was arrested over a year ago by Jordanian intelligence, and was thought to have been flipped to support U.S. and Jordanian efforts against al Qaeda.
The Taliban claimed last week that they had managed to convince a covert agent working for the CIA to change allegiance and instead attack them as a suicide bomber.
Three of the American dead have been identified by their families.
Scott Roberson, 39, of Ohio, was a former Navy SEAL and an undercover narcotics officer for the Atlanta police department. He was married and his wife is pregnant with their first child. He was working as a security officer at the CIA base.
Harold E. Brown Jr., 37, of Virginia, had served in the Army and worked for the State Department. He is survived by a wife and three children ages 12, 10 and 2.
Jeremy Wise, 35, was also a former Navy SEAL. He was from Virginia Beach, Va. His family has posted a memorial page on Facebook.
"He was one of the friendliest people I've ever met," said Amanda Pearson, who attended intelligence training with Wise in the Navy. "He always wanted to help people."
ABC News' Matthew Cole contributed to this report.