
Washington (CNN) - U.S. officials have "specific, credible but unconfirmed" information about a potential al Qaeda threat against the United States coinciding with the 10th anniversary of the September 11 terrorist attacks.
"We have received credible information very recently about a possible plot directed at the homeland that seems to be focused on New York and Washington, D.C.," a senior administration official told CNN Thursday.
New York City is already on higgh alert, with ceremonies set to take place at the World Trade Center cite this Sunday.
This morning on American Morning, Christine Romans talks with New York City Police Commissioner Ray Kelly, who says though there is an increased police presence in the city, it's up to citizens to be on alert as well.
"We have a big city and obviously it's an open city," Kelly says. "That's why we're a functioning and successful city. But we need the public's help. We need them to be vigilant."
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From CNN's Carol Costello:
Even now, a decade later, it's hard to put into words exactly what September 11th means to us. That day, both the pain and the glory of humanity were on display, unfiltered, and in real time.
Talk Back: How has 9/11 changed you?
Let us know. Your response may be read on this morning's broadcast.
The conversation got a little testy between Rick Perry and Mitt Romney in Wednesday night's Republican presidential debate.
The two GOP front runners tried to create some separation on issues like social security and job creation. So who scored and who slipped with the voters?
This morning on American Morning, CNN Contributor Dana Loesch, CNN senior political analyst Ron Brownstein and Newsweek/Daily Beast contributor Mark McKinnon look at who came out on top at the debate.

