AFP - Three men of Afghan origin have been arrested for making false statements to FBI agents investigating an alleged plot to launch an attack on New York, US officials said Sunday.
The US Justice Department said the FBI is also investigating other individuals "in the United States, Pakistan and elsewhere, relating to a plot to detonate improvised explosive devices in the United States," according to affidavits filed to support the arrests.
A bus driver, Najibullah Zazi, 24, and his 53-year-old father Mohammed -- both Afghan natives -- were arrested in the western US state of Colorado late Saturday, the department said in a statement. Ahmad Wais Afzali, 37, also from Afghanistan, was later arrested in New York.
"Each of the defendants has been charged by criminal complaint with knowingly and willfully making false statements to the FBI in a matter involving international and domestic terrorism," the statement said.
The arrests come after raids this week in New York and Colorado and three days of voluntary questioning of Najibullah Zazi in Denver, Colorado.
Investigators focused in the questioning on a alleged plot targeting a major New York transportation hub, such as a subway station, the CNN news network reported on Thursday, citing sources close to investigation.
According to US media reports this week, authorities found 14 new black backpacks in the New York raids that fueled concern the men may have been planning to use the backpacks to carry suicide bombs.
An ABC News report cited unnamed authorities as saying "Zazi brought with him instructions on how to build a bomb using household chemicals."
In a telephone interview with Najibullah Zazi reported in the Denver Post newspaper on Saturday, he denied admitting to any link to Al-Qaeda or involvement in an attack plot.
"It's not true," Zazi told the newspaper. "I have nothing to hide. It's all media publications reporting whatever they want. They have been reporting all this nonsense."
Justice Department officials said Sunday they had intercepted a number of phone calls between Najibullah and Mohammed Zazi and Afzali on September 11, where the defendents discuss Afzali being interviewed by authorities.
Najibullah Zazi told Afzali his car had been stolen and that he feared he was being "watched," according to the affidavits cited by the department.
Afzali then allegedly asked him whether there was any "evidence in his car," to which Najibullah Zazi said no.
In a search of Zazi's rental car in New York, where he had been visiting Afzali, officials said in the affidavits that they found a digital image of handwritten notes "regarding the manufacture and handling of initiating explosives, main explosives charges, explosives detonators and components of a fuzing system."
When asked about and shown the notes, which were found on his laptop computer, Najibullah Zazi "falsely asserted that he had never seen the document before," officials said.
In interviews with FBI agents in Denver, according to the affidavits filed with his detention, Najibullah Zazi meanwhile admitted that on a 2008 trip to Pakistan he "attended courses and received instruction on weapons and explosives at an Al-Qaeda training facility."
Najibullah Zazi, who is a legal permanent resident of the United States, and Mohammed Zazi, a naturalized US citizen, are set to appear in a Colorado federal court on Monday.
On the same day Afzali, also a legal permanent resident, is scheduled to stand before a federal court in New York.
If convicted each man faces eight years in prison.
"The arrests carried out tonight are part of an ongoing and fast-paced investigation," said David Kris, assistant attorney general for national security.