WASHINGTON AND NEW YORK — A federal grand jury in New York indicted a Denver man on a terrorism charge Thursday after federal authorities alleged that he and possibly three others had gone on a buying spree of bomb-making chemicals and were preparing an attack on U.S. soil.
The one-count indictment alleges that Najibullah Zazi, 24, worked for more than a year on a plot to detonate a weapon of mass destruction.
Justice Department documents did not name the alleged co-conspirators, but said that three other Denver-area residents had bought unusual amounts of chemicals from beauty-supply stores, including hydrogen peroxide and acetone, which can be used to make explosives.
In all, authorities are searching for at least a dozen people for questioning in what they describe as the first Al Qaeda-linked plot on U.S. soil since the Sept. 11, 2001, terrorist attacks.
"Zazi remained committed to detonating an explosive device up until the date of his arrest" last Saturday evening, nine days after he arrived in New York City, allegedly to meet with others involved in the plot, according to a Justice Department document.
The document was part of a motion also unsealed Thursday to keep Zazi detained in Colorado without bail. A federal judge agreed, setting the stage for Zazi's transfer to New York to face the terrorism charge.
While Zazi was ordered held, his father, Mohammed Wali Zazi, 53, and Ahmad Wais Afzali, a 37-year-old Queens imam and New York police informant, were ordered released on bail. They were arrested along with Zazi on charges of lying to authorities in the intensive terrorism investigation.
"We will continue to work around the clock to ensure that anyone involved is brought to justice," said Atty. Gen. Eric H. Holder Jr. in announcing the indictment. "We believe any imminent threat arising from this case has been disrupted, but as always, we remind the American public to be vigilant and to report any suspicious activity to law enforcement."
In the last three weeks, Zazi sought "urgent" help in making homemade bombs, according to the detention motion. On Sept. 6 and 7, he allegedly tried multiple times to communicate with another person "seeking to correct mixtures of ingredients to make explosives."
"Each communication," the detention motion alleged, was "more urgent in tone than the last."
Prosecutors said that Zazi had traveled overseas to receive bomb-making instructions and had done extensive Internet research on the components of explosive devices.
They said that on multiple occasions before he arrived in New York City on Sept. 10, Zazi had bought unusually large amounts of components that are used to make TATP (triacetone triperoxide) or other homemade explosives.
TATP is the explosive used in the 2005 London train bombings that killed more than 50 people. It was also intended for use in other Al Qaeda-linked plots, including a 2005 plan to blow up a jetliner traveling from London to the United States and a 2001 plan by Briton Richard Reid to detonate a shoe bomb on a similar flight.
The government alleged that three still-unidentified people purchased unusual quantities of hydrogen peroxide or acetone from beauty-supply stores in the Denver area.
Zazi went twice to the Beauty Supply Warehouse in Aurora, Colo., to purchase highly concentrated hydrogen-peroxide-based products, said Karan Hoss, chief executive of the beauty-supply chain.
Zazi bought 12 bottles of Clairoxide on July 25 and six bottles of Ms. K Liquid 40 Volume on Aug. 28, Hoss said.
Hoss said his employees didn't realize the significance of the purchases until FBI agents visited earlier this month asking questions about anyone who'd made large purchases of hydrogen peroxide. He said they supplied tape and equipment from 48 cameras mounted throughout the store, and agents spotted Zazi.
"Forty-eight cameras in a beauty-supply store is not common. I'm glad we invested the money and were able to provide the evidence, assuming this guy is guilty," Hoss said. "It gives me some comfort. . . . Thank God for good technology and good camera systems."
Authorities also said that they found evidence that Zazi had heated the chemicals on the stove of an Aurora apartment he had rented. Authorities said in court documents that notes on bomb-making found on Zazi's laptop computer discussed heating the chemicals to make them more concentrated.
The documents said that Zazi's fingerprints were on a small electronic scale and batteries like those often used in making homemade bombs.
In public statements, Zazi has denied being part of any terrorist plot. But the FBI alleges that he admitted under questioning to receiving explosives and weapons training by Al Qaeda in the tribal areas of Pakistan that are considered to be the headquarters for the terrorist network headed by Osama bin Laden.
Prosecutors said Thursday that several others had traveled with Zazi to Pakistan last year, suggesting that they too might have received Al Qaeda weapons and explosives training.