State Department issues 'worldwide caution'
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WASHINGTON (CNN) -- The State Department is warning U.S. citizens and employees of an increased possibility of more terrorist attacks coinciding with the second anniversary of the September 11 attacks.
The "worldwide caution," issued Wednesday, warns that al Qaeda is pursuing actions "more devastating" than the deadly plane hijackings two years ago, and said chemical or biological weapons could be used.
The State Department said it is receiving more indications that al Qaeda is preparing to strike U.S. interests overseas. However, a department official said that while there is no credible information of a possible attack, there is a lot of chatter that something is imminent.
"We have got to figure al Qaeda is not sitting on their hands," said the official. "They are out there planning yet another terrorist attack."
Officials said there is evidence terrorists may attempt to strike targets in Baghdad. However, one official said there is other intelligence "suggesting quite a few other places -- none of it is particularly strong."
The worldwide caution came as the Arabic news network Al-Jazeera broadcast what it said was a new statement from al Qaeda leader Osama bin Laden and his top deputy, Ayman al-Zawahiri. The message called on Muslims to attack Americans.
In the tape, the voice purportedly of al-Zawahiri said the United States has experienced "just the first skirmishes" and urged Muslim militants to "attack and devour the Americans and bury them in the graveyard of Iraq."
The CIA has "high confidence" that the voice is al-Zawahiri's, an agency official told CNN. Technical analysis continues on whether the other voice was bin Laden's, the official said.
The tapes were a prime factor in the State Department's decision to issue the warning, counterterrorism officials told CNN. At the same time, they noted there has been an increase in terrorist "chatter" in recent weeks, though nothing to indicate a specific time or place of attack.
Upswings in chatter do not always prompt worldwide cautions. A caution issued April 21 came a few days after chatter decreased and five days after the nation lowered its color-coded, national threat warning system.
But chatter increased before cautions were issued in March, before the United States invaded Iraq, and again in late July. The following month four major terror attacks occurred: the bombings of the Marriott hotel in Jakarta, Indonesia, and in Iraq, a mosque in Najaf and the United Nations headquarters and the Jordanian embassy in Baghdad.
State Department cautions are generally issued for Americans overseas, while alerts, issued by the Department of Homeland Security, pertain to the United States.
The Department of Homeland Security has placed the country on high alert three times in the less than two years since adopting the color-coded threat system. The first was in September 2002. The next time was in February, based on concern that al Qaeda would attempt to attack Americans during or after the Hajj, a Muslim religious period. It also was raised in March, before the United States invaded Iraq.
Following the latest caution, the Bush administration said it does not plan to change the nation's threat level from yellow, or "elevated," to orange, or "high."
In its warning Wednesday, the State Department said U.S. government facilities "remain at a heightened state of alert" and "may temporarily close or suspend public services from time to time to assess their security posture."
The caution said that over the last few months, al Qaeda and its "associated organizations" hit targets in Riyadh, Saudi Arabia; Casablanca, Morocco; and Indonesia. It said Europe and Eurasian locations could be struck.
The caution states "the potential for al Qaeda to attempt a second catastrophic attack within the U.S." cannot be ruled out.
The caution warned that al Qaeda tactics could include "suicide operations, hijackings, bombings or kidnappings. These may also involve commercial aircraft and threats to include conventional weapons, such as explosive devices."
Civilian, as well as official targets, could be threatened, the caution states.
CNN Correspondents Kelli Arena, David Ensor and Jeanne Meserve contributed to this report.