FBI agents have raided the suburban Denver home of the man authorities say is at the center of an alleged al Qaeda plot to carry out attacks in New York.
The agents arrived at the home of 24-year old Najibullah Zazi late this afternoon. One of the agents told ABC News the squad was carrying out a search warrant but declined to comment further.
ABC News has learned that FBI agents in Denver served a search warrant at a second home this afternoon, also located in the suburb of Aurora.
Records show that the home is occupied by Rabia Zazi, the aunt of Najibullah Zazi. FBI Special Agent Kathy Wright would not comment on details of the investigation, but confirmed that the two locations were the only ones searched today."
Watch Brian Ross' report tonight on "World News with Charles Gibson" at 6:30pm.
Zazi's travels to New York last weekend triggered a round of highly publicized raids in the New York area. Authorities told members of Congress the raids had helped to disrupt a plot to carry out a major attack on New York.
Law enforcement officials tell ABC News that agents discovered 14 brand new black backpacks in the New York raids, leading to concern the men may have been planning to use the backpacks to carry suicide bombs.
The men responsible for the attacks on the London subways and the Madrid commuter rail system used backpacks to carry their homemade explosives.
Authorities say Zazi brought with him instructions on how to build a bomb using household chemicals.
Zazi denied to ABC News Tuesday that he had any connections to al Qaeda and said the FBI "got it wrong."
"I have nothing to do with al Qaeda," Najibullah Zazi told ABC News' Denver affiliate. "Any link or anything with al Qaeda."
His attorney, Arthur Folsom, said he planned to take Zazi to the FBI office in Denver today or tomorrow "to remove this dark cloud hanging over him."
Zazi, an Afghan emigree who has lived legally in the United States since 1999, emerged at the center of the case Monday after FBI agents and New York police carried out raids on three apartments in New York where Zazi visited over the weekend.
No charges have been filed, but law enforcement officials told members of Congress they suspected Zazi and the plot were directly connected to al Qaeda, and that Zazi had frequently traveled to Pakistan.
Congressman Peter King (R-NY) said "there is very good reason to believe that there is a connection to Al Qaeda or to Al Qaeda supports."
"[Investigators] would not have moved as quickly as they did if they did not believe there was real potential," King said.
"My client is not a terrorist," Folsom said. He said that "If anything, this is a matter of guilt by association."
Folsom described Zazi as a "quiet and shy young man" who works as an airport taxi shuttle driver in Denver. He said his client visits Pakistan because his wife lives there, in the city of Peshawar near the Afghan border.
Zazi was stopped on the George Washington bridge as he entered New York last Thursday for what he was told was a "routine" drug inspection, although he had not seen any cars stopped before him, his lawyer said.
Two days later, police towed his car away for an alleged "parking violation."
Appearing before a Congressional committee today, FBI Director Robert Mueller said there is no "imminent danger" to New York after the raids.