The White House has no plans to raise the terror threat level on this second anniversary of 9-11, but it is urging people to be on guard against anything suspicious.
The State Department has issued a worldwide warning of possible al-Qaida attacks against U.S. interests, possibly coinciding with the 9-11 anniversary.
White House press secretary Scott McClellan says state and local officials and the private sector should take appropriate security measures under the current threat level, which remains at yellow, or elevated.
The federal government sent out an advisory last week with a reminder of those steps.
McClellan says, "There are still those who are enemies of peace and freedom that seek to harm us."