U.S. intelligence analysts are investigating how much, if anything, Osama bin Laden knew about the plot to blow up a Detroit-bound airliner on Christmas Day, following this weekend’s release of an audiotape from the al-Qaida leader claiming responsibility.
Sources told NBC News that an audiotape released Sunday claiming responsibility for the actions of so-called "underwear bomber" Umar Farouk Abdulmutallab, was made by bin Laden.
However, how much he knew about the plot before the fact is uncertain.
The United States does believe there was some communication between the Al-Qaida high command, known in intelligence circles as “al-Qaida Central” and al-Qaida in Arabian Peninsula, the Yemen-based affiliate that run Abdulmutallab.
The belief is that there was some “strategic guidance” and “consultation” rather than “a day to day tactical relationship,” as one official suggested.
But whether bin Laden himself was informed remains uncertain. At one point the U.S. believed that any attacks on the United States or United Kingdom required specific approval of bin Laden or his Egyptian deputy, Ayman al Zawarhiri. Lately, the thinking is that bin Laden has little if any operational control, acting more as an inspirational figure.
No 'home office' funding
One thing is clear, there’s no indication Al-Qaida Central funded the operation, as it had in the past with other affiliates, officials said. In fact, al-Qaida in the Arabian Peninsula may have more resources than the “home office.”
Instead Al-Qaida central's role is more one of “strategic guidance and consultation" rather than "a day-to-day technical relationship."
In an interview earlier, State Department spokesman P.J. Crowley played down bin Laden's role, saying the tape was an attempt "to continue to appear relevant."
U.S. officials routinely examine such tapes to determine as much as they can about changes in bin Laden's health, demeanor and location.
Abdulmutallab, a Nigerian, told federal agents he had been trained by al-Qaida in the Arabian Peninsula, which is based in bin Laden's ancestral homeland of Yemen.
Bin Laden's tape, which lasted a minute, lauded Abdulmutallab as a "heroic warrior" despite the failure of the attack and said more attempts would be made while the U.S. continued to support Israel.
Abdulmutallab attempted to blow up the airliner as it approached Detroit Metro Airport, but the explosive powder he was hiding in his underwear failed to detonate.
Some intelligence analysts pointed to the use of specific phrases which bin Laden has used ahead of previous attacks as a sign that al-Qaida would take further action over the next year.
However, others noted that almost all of Bin Laden’s and Zawahiri’s messages contain warnings of impending attacks. Officials are currently trying to determine if there are any hints in the message of changes in his health or location.
White House adviser David Axelrod told CNN's "State of the Union" that whatever the source, the message "contains the same hollow justification for the mass slaughter of innocents."
NBC News's Robert Windrem and The Associated Press contributed to this report.