July 17, 2009 -- U.S. intelligence officials were caught "off-guard" by the Friday terror attacks against two U.S.-based hotels in Jakarta, Indonesia.

A senior U.S. official told ABC News the attacks came as a "surprise."

A second U.S. counter-terrorism official said the CIA and other intelligence agencies had given no indication to the White House of "any threat reporting in the last 18 months" involving the Indonesian al Qaeda affiliate, Jemaah Islamiyah.

"Any suggestion that the CIA has not taken the JI threat seriously in recent years is wrong," said a CIA spokesman. "No one from the CIA has ever said that this terrorist group was completely down and out."

U.S. officials had been confident that the group had been dismantled after almost of all its leaders were killed or captured in a joint operation involving Indonesian, U.S. and Australian personnel.

"They were quiet but they weren't dead," said former White House counter-terrorism official Richard Clarke, an ABC News consultant. "They were just playing dead."

U.S. law enforcement officials today said two male suicide bombers were responsible for the attacks on the Ritz Carlton and Marriott hotels in Jakarta. Both bombers had registered as guests at the respective hotels two days ago.

The officials said the attacks were scheduled on a Friday, the Islamic holy day, when most Muslims would likely have been at prayer.

There were no immediate claims of responsibility from Jemaah Islamiyah but they are considered the group most likely to have carried out the attacks given their past history in the region.

"They wanted to send a sign that they are alive and well," said the former U.S. ambassador to Indonesia, Robert Gelbard. "This attack comes shortly after the re-election of the country's president who is committed to fighting Jemaah Islamiyah and al Qaeda."

In voting earlier this month, President Susilo Bambang Yudhoyono won a majority of votes and avoided a run-off in his effort to be elected to a second five year term.

"He has been very effective in making the commitment to not only go after them but also in instituting a wide set of reforms," said Ambassador Gelbard.

Jemaah Islamiyah's most senior commander, known as Hambali, was captured in Thailand in August 2003 shortly after he claimed responsibility for an earlier bombing at the Marriott Hotel in Jakarta. He is currently being held at the U.S. facility in Guantanamo.

Jemaah Islamiyah

The group's second-in-command was recaptured last year after escaping from a prison in Singapore.

"The lesson here is that unless you take out all of the leadership, a group like this will continue to operate," said Clarke. "Every root and branch has to be taken out for the group to be truly dismantled."

Indonesian, U.S. and Australian authorities are now focusing on the group's remaining leader, Noordin Top, who is considered a charismatic recruiter, financier and bomb maker. He was reportedly trained in explosive at an al Qaeda camp in Afghanistan in the late 1990s.

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