The 32-year-old doctor's allegiance was to al Qaeda from the start, however, and not to his Jordanian recruiters or their CIA friends - and it never wavered, a Middle East counterterrorism official told The Associated Press.
He and two other counterterrorism officials gave identical accounts of how and when Humam Khalil Abu-Mulal al-Balawi was recruited.
Jordanian intelligence believed the devout young Muslim had been persuaded to support U.S. efforts against al Qaeda in Afghanistan and wanted al-Balawi to help capture or kill Ayman al-Zawahri, a fellow doctor from Egypt who is Osama bin Laden's right-hand man, according to another counterterrorism official based in the Middle East.
All four spoke on condition of anonymity because they were not authorized to comment on matters involving the CIA and Jordan's national security.
Family and friends said al-Balawi, a father of two young daughters, had practiced medicine in a clinic at a Palestinian refugee camp near Zarqa, the hometown of slain al Qaeda in Iraq leader Abu Musab al-Zarqawi. One high school classmate, Mohammed Yousef, described al-Balawi as "brilliant," well-spoken and well-mannered, though he kept mostly to himself and did not mingle much with relatives or friends.
The doctor also spoke openly about wanting to die in a holy war, Yousef said, adding that in Internet postings he called tirelessly for jihad against Israel and the United States.
"What landed him in jail was his online activities," says CBS News' Khaled Wassef, who monitors jihadist Web forums and chat rooms. "He says that he has always dreamed of being a martyr."
"If the love of jihad entered a man's heart, it will not abandon him, even if he wanted so," al-Balawi said in an interview published by the Ana Al-Muslim, or "I, the Muslim," Web site.
Jordanian intelligence was aware of these provocative statements when they arrested al-Balawi last March after he signed up for a humanitarian mission to the Gaza Strip with a Jordanian field hospital in the wake of Israel's offensive there, the counterterrorism officials said.
Al-Balawi was jailed for three days and shortly after that, he secretly left his native Jordan for Afghanistan, they said, suggesting he had agreed to take on the mission against al Qaeda.
Once in Afghanistan, al-Balawi provided valuable intelligence information that helped foil al Qaeda terror plots on Jordan, the officials said. His Jordanian recruiters then offered al-Balawi to their CIA allies as someone who would help them capture or kill al-Zawahri.
He had provided bona fide information, including the location of al Qaeda leaders killed by CIA drone strikes, but a U.S. intelligence official says "there were still questions" about his "reliability" and the "access" he claimed to have to senior al Qaeda leaders, reports CBS News chief national security correspondent David Martin.
On Dec. 30, the Jordanian was , a tightly secured CIA forward base in Khost province on the fractious Afghan-Pakistan frontier, according to a former senior U.S. intelligence official and a foreign government official.
He was not closely searched, according to former and current U.S. intelligence officials, apparently because of his perceived value as someone who could lead American forces to senior al Qaeda leaders.
Shortly after the debriefing began, al-Balawi set off his explosives, a former U.S. intelligence official said. The blast and Ali bin Zaid, a senior Jordanian intelligence officer and relative of Jordan's King Abdullah II.
"The Jordanians have managed to get agents inside these very difficult to enter al Qaeda cells and deliver real intelligence," journalist and novelist David Ignatius, author of "Body of Lies," about the CIA and Jordanian intelligence, told CBS News.
Ignatius thinks the .
"One thing that's obvious is that we're so hungry for information about the location of Osama bin Laden and his number one deputy, it's clear we would just leap at any opportunity we saw to get a fix on where they were," he told CBS.
Yousef, al-Balawi's high school friend, said the doctor had deceived family and friends, telling them in March he was going to Turkey for medical studies and to be with his wife, a Turkish journalist.
"He fooled us, saying he was going to continue his medical studies, but he embarked on a suicide mission," said a close relative, who requested anonymity, citing instructions from Jordanian authorities to the family not to talk to the media. "He never called us," the bearded relative said, weeping.
He said the family found out about al-Balawi's death in a telephone call last Thursday from a man who claimed to be from the Taliban.
A Jordanian official denied al-Balawi was a double agent, saying he was a sometime contact of Jordanian intelligence who had no formal role as an intelligence officer. The official spoke on condition of anonymity to discuss the government's sensitive intelligence contacts.
The official said al-Balawi had been arrested by Jordanian authorities about a year ago and was investigated before being released for what the official said was a lack of evidence.
The official said al-Balawi then traveled to Pakistan, saying he planned to study there, and contacted Jordanian authorities by e-mail soon after. Al-Balawi claimed to have important information about al Qaeda plans to target Jordanian interests, the official said.
Jordan shared that information with the United States, and maintained contact with al-Balawi electronically, the official said, adding that Jordan has no confirmation that al-Balawi was the suicide bomber.
Still, the case raises uneasy questions about how the CIA could have been duped for so long.
A U.S. intelligence official said Tuesday the danger of using informants is inherent but unavoidable. He said intelligence agencies have to rely on unsavory individuals to penetrate terrorist groups because no one else has the access.
He said those hazards were neither denied nor ignored by the CIA officers. He spoke on condition of anonymity because he was not authorized to discuss the matter publicly.
Questions also remain about why the bomber was not searched for weapons or explosives prior to his meeting with CIA officers, which is standard protocol even for visiting dignitaries, said a senior foreign government official and more than a dozen former CIA officers.
Also unclear is why so many people were present for the debriefing. For physical security reasons and to protect the identities of both informants and CIA officers, debriefings are generally conducted with two or three people.
Former CIA officers said the large group and failure to screen for a bomb suggest a lapse in what the CIA calls "tradecraft" - standard operating procedures meant to maximize security, secrecy and intelligence gathering.
The Pakistani Taliban has claimed they used a turncoat CIA operative to carry out the attack, saying it was in revenge for a top militant leader's death in a U.S. missile strike.
It was impossible to verify the claim independently, but it is highly unusual for the Pakistani Taliban to claim credit for an attack in Afghanistan.
Michael Scheuer, former head of the CIA unit that tracked bin Laden, said it's inconceivable that the bombing could have been carried out without the knowledge of the al Qaeda-linked Haqqani network. The autonomous Afghan Taliban faction - whose leader was once a U.S. ally - is a serious threat to American and NATO troops in Afghanistan's east and operates on both sides of the border with Pakistan.
"There is no way this operation would have occurred in Khost without the knowledge and active support of Jalaluddin (Haqqani) and/or his son," Scheuer said. "They and their organization own the area - and especially right around Khost - and nothing occurs that would impact their tribe or its allies without their knowledge and OK. Both men, moreover, would be delighted to help bin Laden in any way they can."
The bombing - the worst attack against the CIA in decades - exposed the close cooperation between Jordanian intelligence and the CIA, which has for decades helped fund and train Jordanian operatives.
In return, Jordan has acted as a proxy jailer for the CIA, interrogating several al Qaeda militants who were flown in on rendition flights from the U.S. military prison at Guantanamo Bay, Cuba.
A key U.S. ally in the Middle East, Jordan has consistently offered intelligence to the United States on militants and helped track down Jordanian-born al-Zarqawi, who was killed in a U.S. air strike in Iraq in June 2006.
Jordan has a vested interest to fight al Qaeda, which has plotted several deadly attacks against the pro-U.S. Arab kingdom. The plots included a bungled attempt to bomb the U.S. Embassy and tourist attractions during Millennium celebrations in Jordan and a 2004 foiled attack using chemicals on the Amman headquarters of the Jordanian intelligence, which experts said would have killed thousands.
The bombing of the CIA base was an embarrassment for Jordan.
The country's pro-U.S. government has gone to great lengths to conceal its connection with the attack on the CIA to avoid angering Arabs already disgruntled with Washington's Mideast policy, which they regard as biased in favor of Israel.
Al-Balawi came from a nomadic Bedouin clan from Tabuk, in western Saudi Arabia, which has branches in Jordan and the West Bank. He was born in Kuwait in 1977 to a middle-class family of nine other children, including an identical twin brother. He lived there until Iraq's 1990 invasion of the rich Gulf nation when the family moved to Jordan. He graduated with honors from an Amman high school and studied medicine in Turkey.