New details have emerged over the international scope of the investigation into Najibullah Zazi's alleged bomb plot.
Sources tell the Associated Press the CIA learned through one of its informants that he was in communication with a senior al-Qaida operative.
The agency then alerted domestic agencies, and President Barack Obama was reportedly briefed as officials crafted their case against Zazi.
The involvement of the CIA's counterterrorism squad separates the case from most terror investigations, which begin with domestic suspicions.
The FBI says the Afghan immigrant tried to make a homemade explosive to detonate in the city.
Zazi is being held without bail on charges of conspiracy to detonate a weapon of mass destruction.
He has pleaded not guilty.