The World Economic Forum opened Thursday in New York, Mardi Gras celebrations are taking place as New Orleans readies for Sunday's Super Bowl, and the Olympic Games begin next week in Salt Lake City.
And all that comes as prisoners and documents captured in Afghanistan disclose that al-Qaida had scouted numerous targets in the U.S. besides the World Trade Center including water treatment plants, nuclear power facilities and major airports, all of which remain under heightened security.
Government officials said Thursday that nuclear power plant operators were alerted last week that terrorists might be planning an airplane attack on a reactor. The Nuclear Regulatory Commission based its alert on information from an al-Qaida operative, the officials said.
The alert said "the attack was already planned" and three people already "on the ground" were trying to recruit non-Arabs to take part, one official said, speaking on condition of anonymity.
However CBS News has learned that everything the government knows about this latest threat comes from a single source and is apparently two or more months old.
The information came to light again because it was picked up by a foreign government and relayed to the U.S. as new information.
Secretary of Defense Donald H. Rumsfeld said Thursday, "we're spending a lot of money and we're spending a lot of time trying to make sure that we take reasonable steps to protect our nuclear power plants."
New Orleans has never had the game and Madri Gras parades at the same time. And now, for the first time as well, the Super Bowl has also been designated a National Special Security Event. That means twice the usual police will be on hand and the Secret Service will use face-recognition technology to scan the crowd.
In Utah, it'll be more of the same just a lot more of it. Dozens of sites at the Winter Olympic Games will be monitored live back at FBI headquarters in Washington.
FBI Director Robert Mueller said Thursday his agency had "moved heaven and earth" to make the Super Bowl and the Olympics safe and secure.
"We're still in a high state of alert and will be for some time," he said.
Thousands of police, national guard troops, FBI and Secret Service agents have taken up positions around Salt Lake City in what has been called the biggest security operation ever put in place for a sporting event.
The airports will be shut down during opening and closing ceremonies, and Olympic planners are mindful that in addition to 2,500 athletes and 70,000 visitors a day they'll have two special guests.
"For opening ceremonies the president's going to be there. Closing ceremonies, the vice president is going to be there," said Olympic Security Chief David Tubbs.
Officials tried to downplay the latest security warnings, but it' clear that 9/11 is on their mind.
"I mean, goodness, the Super Bowl's going to go on," said Rumsfeld. "People go out and do their things. On the other hand, we're realistic."
Mueller said the United States remained on a "very high state of alert" in part because of documents recovered in Afghanistan that had helped identify unspecified plots. He declined to elaborate.
In his State of the Union address to Congress Tuesday, President Bush said the documents found included diagrams of American nuclear power plants and public water facilities, detailed instructions for making chemical weapons, surveillance maps of American cities and descriptions of landmarks in America and throughout the world.
Recent news reports have cited authorities as saying Muslim extremists have identified a number of potential U.S. targets, including Seattle's landmark Space Needle, for possible future attacks.
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