London Telegraph 
Sept 9, 2011
US intelligence officials said they had detected a potential terrorist plot timed to coincide with the tenth anniversary of the September 11 attacks.
Security is to be heightened in New York City and Washington, DC, after a “specific, credible but unconfirmed” threat was discovered, according to a statement issued by the Department of Homeland Security.
ABC News reported that officials believe the alleged plot was initiated by the new al-Qaeda chief, Ayman al-Zawahiri, who pledged to avenge the death of Osama bin Laden earlier this year.
Janice Fedarcyk, FBI Assistant Special Agent, said: “al Qaeda has shown an interest in important dates and anniversaries. In this instance it is accurate that there is credible, specific but unconfirmed information.”
President Barack Obama was briefed on the information earlier on Thursday and requested that counterterrorism officials step up their response to the suspected threat, according to White House spokesmen.