WASHINGTON (CBS 2/AP) — The Obama administration on Sunday warned Americans of potential terrorist threats in Europe and urged them to be vigilant in public places, including tourist spots and transportation hubs. As CBS 2HD’s Kathryn Brown reports, some tri-state residents were taking the warning in stride.

“Personally I’m reasonably careful wherever I go,” said Nicola Roe, who’s traveling to London.

“The threats are going to be there. We just have to be courageous and move on and ignore them,” said Matthias Kwenin, also traveling to London.

“Current information suggests that al-Qaida and affiliated organizations continue to plan terrorist attacks,” it said. “European governments have taken action to guard against a terrorist attack and some have spoken publicly about the heightened threat conditions.”

CBS2HD reached Long Island Congressman Peter King by phone. He’s the ranking member of the Committee on Homeland Security.

“It’s probably the most serious potential series of attacks we’ve seen in Europe in some time,” Rep. King said. “It could be any number of European cities and that’s the basis for the cause of concern.”

New York City Mayor Michael Bloomberg stressed that no threats should be ignored.

“We take everything, no matter where it happens in the world, seriously,” Mayor Bloomberg said. “That is why [NYPD] Commissioner [Ray] Kelly, many years ago, stationed New York City police officers at major cities around the world.”

A State Department travel alert advises U.S. citizens living or traveling in Europe to take more precautions about their personal security. The alert is one step below a formal travel warning advising Americans not to visit Europe.

Sunday’s alert noted in particular “the potential for terrorists to attack public transportation systems and other tourist infrastructure.”

“We know that al-Qaida and its network of terrorists wishes to attack both European and U.S. targets,” Secretary of State Hillary Clinton said.

Security experts believe Osama Bin Laden and other senior Al-Qaida leaders may be behind the alleged plot. A new 13 minute tape recorded by Bin Laden was just released on the internet that was recorded recently enough to reference the floods in Pakistan.

“U.S. citizens should take every precaution to be aware of their surroundings and to adopt appropriate safety measures to protect themselves when traveling,” the department said.

U.S. and European security experts have been concerned for days that terrorists may be plotting attacks in Europe with assault weapons on public places, similar to the deadly 2008 shooting spree in Mumbai, India.

The plot may target sites in major cities in Great Britain, France, Germany, and perhaps Denmark. The attacks could involve assault weapons used in public places, similar to the 2008 shooting spree in Mumbai, India.

The alert did not urge travelers to stay away from public places. The Obama Administration and European officials view that as an overreaction.

If Bin Laden is involved, it could be his biggest operational role in planning an attack since 9/11.

(© 2010 CBS Broadcasting Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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