A senior official with Iraq's interior ministry told CNN on condition of not being identified that top officials of al Qaeda in Iraq, including Adnan Ismail Najim Abdullah al-Dulaimi, escaped from Abu Ghraib prison during the jailbreak there last month and remains at large.
Bergen noted that a 2006 prison break in Sanaa led to the creation of al Qaeda in the Arabian Peninsula, one of the terrorist organization's most virulent affiliates.
Although the prison breaks are not the main reason for the raised terror threat, said CNN Terrorism Analyst Paul Cruickshank, "it is part of the background music." Prison breaks can often strengthen terrorist groups because "some of these guys are likely to be seasoned operatives," he added.
To CNN National Security Contributor Frances Fragos Townsend, the timing of the prison breaks and increased intelligence chatter building up to the end of Ramadan signaled heightened al Qaeda activity that required precautionary steps in response.
She noted that in the run-up to the September 11, 2001, terrorist attacks, "the government failed to connect dots."
"These seem like dots that ought to be connected," said Townsend, a former homeland security and anti-terrorism adviser to the Bush administration. "You can figure out later whether or not you were right."
Another dot she cited was that al-Zawahiri recently appointed Wuhayshi to be the new general manager of the global al Qaeda network.
A high-profile attack orchestrated by Wuhayshi would cement the Yemeni's new position in the al Qaeda hierarchy, Townsend said.
According to a U.S. official with access to the latest intelligence, Wuhayshi's appointment as a top global al Qaeda figure would almost certainly have required back-and-forth communication between AQAP and al Qaeda central.
Over the weekend, Interpol warned that al Qaeda has been tied to the prison breaks on July 23 in Iraq, on July 26 in Libya and four days later in Pakistan.
End of Ramadan
Another factor prompting the embassy and consulate closures is the end of Ramadan. Depending on when a new crescent moon is seen, the Muslim holy month could end Wednesday or Thursday.
Ramadan's end is celebrated with the Eid al-Fitr festivities -- a three-day holiday in most Muslim countries.
The State Department, in announcing its embassy and consulate closures, said "a number of our embassies and consulates were going to be closed in accordance with local custom and practice for the bulk of the week for the Eid celebration at the end of Ramadan."
Townsend said there could be a strategic reason for shutting down the diplomatic offices.
"Once you take targets away, it buys you additional time to try and disrupt, to identify the cell, the operators in country and the region, and work with your partners in the region to try and ... get them in custody or disrupt the plot," she said. "So, some of this operationally is about buying time."
List of closures
A total of 19 U.S. embassies and consulates will be closed Monday through Saturday.
The following 15 were part of the original list of 20 diplomatic facilities closed Sunday:
U.S. Embassy Abu Dhabi, United Arab Emirates
U.S. Embassy Amman, Jordan
U.S. Embassy Cairo, Egypt
U.S. Consulate Dhahran, Saudi Arabia