AMMAN, JORDAN - The plan was to unleash mayhem across an entire city and "bring Amman to its knees," in the words of one security official. It would start with suicide bombings at two shopping malls, then build momentum as teams of terrorists blew up cars and raked cafes with machine-gun fire.
In the midst of the ensuing chaos, the attackers would turn their attention to the U.S. Embassy, the primary target and a long-sought prize for the organization that investigators say provided critical support for the scheme: Al-Qaida's affiliate in Iraq. Using the terrorist group's expertise and weapons from Syria's civil war, the plotters planned to rain mortar shells on the U.S. compound and homes nearby.
"They wanted to kill as many as possible -- Muslim and Christians," said a Jordanian official, speaking on the condition of anonymity to discuss an ongoing probe into the most serious terrorist plot uncovered here in nearly a decade.
Jordanian authorities foiled the plot last month, arresting 11 men said to be the ringleaders. Although the suspects are Jordanians, the investigation has affirmed the key role played by Al-Qaida's Iraqi branch, commonly known as AQI, which analysts say is rebounding after being all but destroyed by U.S. troops in the past decade.
New evidence shared by security authorities here, including intercepted e-mails, shows that the terrorist cell received guidance from AQI. The instructions included recipes for powerful explosives intended to blow up shops, restaurants and embassies, according to Western and Middle Eastern officials briefed on the investigation.
The same kinds of explosives also are turning up in Syria, intelligence officials and terrorism experts say, underscoring AQI's expanding role in that country's 20-month-old civil war.
Equally worrisome, analysts say, is Syria's emergence as a training ground for Islamist fighters from outside the country, including some who are linked to AQI. A Western intelligence official familiar with the Amman plot said most of the suspects had fought in Syria before returning to Jordan with new skills and a changed perspective toward their native country.
The reemergence of AQI comes at a time when U.S. officials and analysts are expressing growing concern about other Al-Qaida affiliates, including Al-Qaida in the Arabian Peninsula, which operates in Yemen, and Al-Qaida in the Islamic Maghreb, which operates in North Africa. U.S. intelligence officials have said that some of the fighters involved in the Sept. 11 attack on the American diplomatic outpost in Benghazi, Libya, were associated with the North Africa branch.
The Jordanian plot, revealed by the kingdom's officials on Oct. 21, is described as the most ambitious in the country since Nov. 9, 2005, when suicide bombers linked to AQI simultaneously struck three Amman hotels, killing 60 people and wounding more than 100.
In interviews over several days, Jordanian officials said the scheme was hatched during the spring and summer by 11 Jordanians connected to the Salafi movement, an ultraconservative, puritanical sect within Sunni Islam with growing numbers of followers throughout the Middle East.