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Investigation: Following the money trail

SUMMARY:

Treasury Secretary Paul O'Neill said Sunday efforts to trace the financing of terror groups are turning up an increasing number of money sources.

Abdullah Mohammed Binladin, among the youngest of Osama bin Laden's 50 surviving siblings, reiterated his family's condemnation of the man suspected of orchestrating the September 11 attacks on the United States in an interview with The Boston Globe published on Sunday.

The massive task that confronts U.S. investigators in the aftermath of the attacks on New York and the Pentagon -- and the urgency of stopping future acts from being carried out -- is putting a new premium on the ability of federal, state and local officials to work together: It's prompting calls for improvement in a relationship that historically has been marked by friction and turf battles.

Two senior United States law-enforcement sources tell CNN that known and suspected members of terrorist cells have been monitored in recent days -- in activities that mirror those taken by the suspected hijackers and their associates in the days preceding the September 11 attacks on the World Trade Center and the Pentagon.

UPDATE:

In a televised interview, O'Neill was asked about reports that there may twice as many groups as previously believed funneling money to Saudi dissident Osama bin Laden, whom the U.S. has named the prime suspect in the September 11 attacks on New York and Washington.

"Yeah, and we're probably not at the end of our discovery process," O'Neill said. (Full story)

Abdullah Mohammed Binladin, 35, has spent much of the last decade living in the Boston area earning a master's and doctoral degrees in law from Harvard University.

•  Summary   •  Update   •  Key questions   •  Who's who   •  Impact  CNN.COM SPECIAL REPORT  CNN NewsPass Video  Agencies reportedly got hijack tips in 1998  MORE STORIES Intelligence intercept led to Buffalo suspects Report cites warnings before 9/11  EXTRA INFORMATION Timeline: Who Knew What and When? Interactive: Terror Investigation Terror Warnings System Most wanted terrorists What looks suspicious? In-Depth: America Remembers In-Depth: Terror on Tape In-Depth: How prepared is your city?  RESOURCES On the Scene: Barbara Starr: Al Qaeda hunt expands? On the Scene: Peter Bergen: Getting al Qaeda to talk

"Our name is being hijacked," he told the Globe in an interview at his Cambridge, Massachusetts, apartment. "It is a big family. There is a black sheep in every big family."

All 11 other Binladin relatives in the Boston area, Abdullah's nieces and nephews boarded a chartered Saudi jet and left Boston on September 19, he said, adding that most of the family uses the Binladin spelling. (Full story)

Much has been said since the attacks of the need to streamline the flow of communication and intelligence sharing among federal agencies, such as the FBI and the CIA. But some officials and analysts are also pointing to a need for greater collaboration vertically, among all levels of law enforcement -- federal, state, and local -- in order to better confront the new challenges posed by terrorists operating within the United States. (Full story)

Law-enforcement sources stressed there was no evidence of "a specific threat" from monitored terrorist cell members but, in the words of one, the intelligence information "adds to the sense of unease" among law-enforcement and other government officials.

A second official said the suspicious activities have included travel into and out of Afghanistan, and that the monitored conversations and other activities that have raised concerns "are much more overseas than here" in the United States. (Full story)

KEY QUESTIONS:

How is law enforcement working globally to coordinate the investigation?

How will the expansion of law-enforcement powers affect Americans' civil liberties? Click here for more.

How are people identified as suspected terrorists communicating with each other? Click here for more.

How are law-enforcement authorities using technology such as encryption tools to hunt terrorists? Click here for more.

What groups are U.S. investigators focusing on, and what are their aims? Click here for more.

How would law-enforcement authorities go after financial assets of people identified as terrorists? Click here for more.

How did the September 11 attackers evade U.S. intelligence? Click here for more.

WHO'S WHO:

George W. Bush: U.S. president

Colin Powell: U.S. secretary of state Click here for more

Condoleezza Rice: National security adviser Click here for more

John Ashcroft: U.S. attorney general

Robert Mueller: FBI director Click here for more

George Tenet: CIA director. Click here for more

Osama bin Laden: U.S. authorities have named bin Laden, a wealthy Saudi exile living in Afghanistan, as the prime suspect in masterminding the September 11 attacks. Click here for more

IMPACT:

Information gained from the investigation could lead to fundamental changes in U.S. security and intelligence systems, as well as surveillance laws.