The White House said Monday that a new terror threat against Europe isn't related to the United States.
Press Secretary Robert Gibbs said that Americans traveling abroad should take commonsense precautions, but he emphasized that people were not being told to stay home.
Gibbs told reporters that President Barack Obama was briefed on the situation Saturday. On Sunday, the U.S. issued an alert to Americans living in or traveling to Europe to be vigilant because of the threat of terrorism there.
The threat "deals with Europe and isn't related to the United States," Gibbs said, without providing details.
"We are concerned enough to alert those who are in Europe to be alert to their surroundings," the spokesman said at a White House briefing. Gibbs said people should be alert to suspicious activities and should be aware of where to go in an emergency.
Earlier, the FBI and Homeland Security Department said they had have no indication terrorists were targeting the U.S. or its citizens as part of a new threat against Europe.
According to an intelligence bulletin obtained by The Associated Press, the FBI and Homeland Security said they believe the al-Qaida terrorist network continues to want to attack the United States, but there is nothing pointing to anything specific, imminent or related to the European plots. They warned law enforcement authorities to be on the lookout for suspicious activity, as it's more difficult to detect terror plots carried out by individuals or small groups.
"We are aware of, and closely monitoring, recent reporting indicating a terrorist threat to Europe," the bulletin said. "At this time, there is no indication that the reported threat is directed specifically toward the United States, its citizens, or infrastructure; however, we assess that al-Qaida and its affiliates continue to plot against the Homeland and US allies."
Former Homeland Security Secretary Michael Chertoff said Americans planning trips to Europe needed to pay close attention to the security alert.
Chertoff, who headed the agency during George W. Bush's presidency, said the State Department's alert means that tourists should take commonsense precautions, such as knowing where they are and identifying an exit strategy if necessary.
Chertoff was interviewed in the wake of the Obama administration's decision to release a travel alert Sunday in response to reports of a possible terrorist threat against Britain, France and Germany. He advised travelers to consider "where would you take shelter if something happened." And Chertoff also says: "Don't walk around with the American flag on your back."
"As you know they haven't raised the alert level here," he noted in an interview on ABC's "Good Morning America."
"The first thing officials do when they get this kind of threat information," he said, "is to ask whether there is any connection."