DENVER, Colorado (CNN) -- A Colorado resident at the center of a federal terrorism probe met with FBI agents for a second day Thursday, as his lawyer disputed a report that bomb-making plans were found on the man's computer.
FBI agents search the apartment of Najibullah Zazi on Wednesday in connection with a terror investigation.
Federal agents searched Najibullah Zazi's apartment and another home in the same Denver suburb on Wednesday in connection with the terrorism probe, which emerged Monday with a series of raids in the New York borough of Queens. A law enforcement official told CNN that diagrams showing how to make bombs were found on the computer Zazi had with him when he was stopped in New York during a recent visit, but his lawyer, Arthur Folsom, dismissed that allegation.
"There's no diagram of a bomb. There's no information like that," Folsom told reporters while walking his client to his second meeting with federal agents. If something like that had turned up on Zazi's computer, he said, "Do you really think the FBI would have allowed us to walk out of here last night?"
Zazi, an Afghan national, gave writing, fingerprint and DNA samples to FBI agents Wednesday during a "very friendly, very cordial" interview, Folsom said. He said Zazi has no ties to terrorism, and he believes his client drew investigators' attention "because he stayed at a house owned by an old friend of his who was under observation from the FBI."
But according to law enforcement sources with knowledge of the investigation, the Colorado searches were part of a probe that began with Zazi and led to New York.
A former counterterrorism official briefed on the investigation also said bomb instructions were found, but could not say where. The former official said backpacks, computers and maps were found during the searches in New York, and field tests turned up positive for explosives. But initial tests often yield false positives, and the former official was unaware whether more definitive tests had been concluded.
The case began with a New York police informant, with authorized FBI wiretaps used to further develop the case, the former counterterrorism official said. Agents launched the raids after police stopped Zazi on the George Washington Bridge during a recent visit to New York, raising concerns that he would figure out he was under surveillance, the former official told CNN.
Wednesday, Folsom said Zazi stayed in one of the apartments that was raided after he drove to New York from Denver to sort out a business issue. Sources close to the investigation told CNN that the Queens raids were spurred by a confluence of events in the city -- including the upcoming U.N. General Assembly session and President Obama's Wall Street speech on Monday.
It's believed to be the first time Afghan nationals are suspected of possible involvement in an alleged terror plot targeting the United States. But FBI director Robert Mueller told a Senate committee Wednesday that he did not believe the investigation had revealed any "imminent danger."
CNN correspondents Ted Rowlands in Denver and Jeanne Meserve in Washington contributed to this report.