NEW YORK -- The FBI warned city officials Tuesday it had received uncorroborated information that terrorists have made threats against New York and some of its landmarks, including the Statue of Liberty and the Brooklyn Bridge.
Police Commissioner Raymond Kelly characterized the information as "general threats" but patrols were increased at some popular sites, including the statue and the bridge.
A law enforcement official said the information came from an unidentified detainee who spoke with the FBI.
The FBI in a statement said it had no information on the date or method of a possible attack, but had alerted New York officials "out of an abundance of caution."
The warning came one day before the start of Fleet Week, an annual maritime celebration expected to draw 6,000 naval personnel to the city through the Memorial Day holiday weekend.
It also comes about a week before the city plans to end search and recovery work at the site of the World Trade Center, where more than 2,800 people died in the Sept. 11 terrorist attacks.
Kelly said police were prepared for "any eventuality."
"We are taking all necessary precautions and are communicating with the appropriate law enforcement agencies on both the state and federal levels," he said.
Security was increased around monuments and landmarks after the warning was relayed to New York, the official said. Kelly would not confirm any details, but heightened security was visibly in place at City Hall and the Brooklyn Bridge.
The city is preparing for Fleet Week 2002, an annual gathering that this year boasts the largest number of U.S. Naval vessels ever sent to New York City by an Atlantic Fleet commander.
Sailors, Marines and Coast Guard personnel will be aboard 22 ships, including six warships.
The public is invited aboard ships participating in the festival.
Gov. George Pataki urged people to visit New York despite the threats.
"We cannot allow threats to take away our freedom or our confidence," Pataki said. "There are going to be threats for the foreseeable future."
Pataki said the state has received all types of threats over the past eight months, but state and city officials have taken security steps.
He said the threats were aimed at "dividing us and frightening us and taking away our freedom by fear."
Nearly every major tourist attraction, including all the big museums, the Empire State Building and the Statue of Liberty, were closed following the Sept. 11 attack on the World Trade Center.
Liberty Island, home to the Statue of Liberty, and Ellis Island -- both national parks -- were closed to visitors for 100 days after the attacks.
The statue itself remains closed.
Security zones also remain in place, barring vessels from operating within 150 yards of the United Nations building, Ellis Island or Liberty Island. Also, no vessels can operate within 25 yards of bridge piers, abutments, tunnel ventilators or waterfront facilities. Additional restrictions were announced Monday for Fleet Week.
Mayor Michael Bloomberg said he didn't see any reason why people shouldn't enjoy Fleet Week and other activities over the weekend.
"The more people that are out the safer this city will be, and we are used to hosting big events. Fleet Week is just another one," he said. "There are always threats unfortunately, but fortunately, most are hoaxes."
New Yorkers seemed to be taking the warning in stride.
"I think if you are going to live in New York, you're not going to let your life be dictated by crazy people," said Evelyn Krasnow, 31, outside a Starbucks coffee shop in midtown Manhattan.