Threat level to remain at 'orange' through holiday
Security stepped up around nation amid warnings
WASHINGTON (CNN) -- The nation's terror threat level will remain at "orange," or high, at least through the Memorial Day holiday weekend or "until we are confident al Qaeda's planning activities have slowed down or been disrupted," a Bush administration official said Thursday.
The official said intelligence "chatter" remains high, but not specific. He said there is no new intelligence that he is aware of, and no reason to change the assessment of the intelligence that led to the hike in the threat level Tuesday.
U.S. officials said intelligence pointed more toward a strike in the Persian Gulf region than in the United States.
A U.S. government official said one factor contributing to the threat level change was intelligence relating to the activities of al Qaeda members in Iran.
Intercepted communications picked up around the time of last week's near simultaneous car bombings at three residential compounds in Riyadh, Saudi Arabia provide evidence, some U.S. officials said, of an operational post in Iran.
Iranian officials Thursday told a U.N. representative that Iran has several unnamed al Qaeda operatives in custody, CNN has learned.
The acknowledgment comes as Washington has intensified its accusations that al Qaeda terrorists are inside Iran -- something Tehran had previously denied. (Full story)
With the U.S. terror threat alert at its second-highest level, a familiar San Francisco landmark was the scene of a training exercise Thursday for Bay area emergency agencies.
The exercise at the Golden Gate Bridge had been planned before the alert level was raised to orange on the color-coded system. (Raising and lowering threat level)
The bridge represents the type of "soft" target that emergency preparedness officials have said concerns them.
The drill was designed to test agencies' readiness to respond to earthquakes, hazardous-materials spills and terrorist attacks. Portions of the bridge and nearby bike trails around it were closed with the alert level change, and additional security patrols were dispatched.
In the face of intelligence warnings about attacks, the Pentagon has raised the "air defense posture" in the Washington area by deploying anti-aircraft missiles around the capital and stepping up air patrols, defense officials said.
Across the country, police chiefs also said they were increasing patrols and instituting other security measures.
In New York, the heightened alert coincides with the start of the annual Fleet Week observances, during which some 3,500 sailors and Marines are expected to be in the city for athletic competitions, receptions, concerts and free public tours of the ships. (Full story)
Separately, the Defense Intelligence Agency increased its terrorism threat level from significant to high, its top level, officials said. The threat assessment is issued to U.S. military commanders worldwide, who then review security procedures at their facilities. (Full story)
CNN Correspondents David Ensor, John King, Sheila MacVicar and Barbara Starr and Producer Terry Frieden contributed to this report.