Terrorism suspect Najibullah Zazi plotted for more than a year to detonate homemade bombs in the United States, had recently bought bomb-making supplies from beauty supply stores and was looking for "urgent" help in the past two weeks to make explosives, an indictment charged Thursday. Zazi, arrested in Denver last weekend on a count of lying to terrorism investigators, was charged in New York with conspiracy to use weapons of mass destruction. He appeared in a Denver courtroom Thursday on the lesser charge. The two-page indictment offers few details, but a separate document - a government motion seeking to deny bail to the 24-year-old Afghan immigrant - lays out evidence gathered by investigators. The airport shuttle driver began plotting to "use one or more weapons of mass destruction" between Aug. 1, 2008, and September 2009 against the United States, the papers say. The papers offer few specifics on where and when an attack might have been planned, but counterterrorism agents fear he and others might have been planning to detonate homemade bombs on New York City commuter trains. The document says that on Sept. 6 and 7, Zazi tried to communicate with another individual "seeking to correct mixtures of ingredients to make explosives." "Each communication," the papers say, was "more urgent than the last." On those days, Zazi rented a suite at a hotel in his hometown of Aurora, Colorado, authorities charge. The room had a kitchen, and subsequent FBI testing for explosives and residue in the suite found the presence of residue in the vent above the stove. In July and August, Zazi bought unusually large amounts of hydrogen peroxide and acetone products from beauty supply stores in the Denver metropolitan area, the document says. He searched the Internet for home improvement stores in Queens before driving a rental car for a two-day trip to the city, the document says. Zazi has publicly denied any terrorist plotting - and the documents do not specify a specific time and place of a possible attack. The arrests were followed by a flurry of nationwide warnings of possible strikes on transit, sports and entertainment complexes. But a series of searches in Denver and New York City over the past two weeks - including high-profile raids on Queens apartments that netted backpacks, cell phones and a scale - have not found any evidence of explosives. Law enforcement officials have said Zazi might have been plotting with others to detonate backpack bombs on New York trains in a scheme similar to the deadly attacks on the London subway and Madrid's rail system in the last few years. John Choy, a salesman for 707 Beauty Supply and Fashion Plus in the Denver suburb of Aurora, said FBI agents came to his store about two weeks ago and asked him whether he sold hydrogen peroxide to anyone recently. Choy said that the store sells only a few small bottles a year and that no one who bought it fit the description of Zazi. Authorities planned to transfer Zazi to the federal court in the New York borough of Brooklyn to face the new charge. Zazi; his father, Mohammed; and a New York City imam were appearing Thursday in Denver and Brooklyn courts on counts of lying to terrorism investigators. The imam, Ahmad Wais Afzali, was released on $1.5 million bond after a hearing Thursday. A second, unrelated indictment unsealed Thursday in the same court charged a Brooklyn man with supporting terrorism. An indictment alleges Betim Kaziu traveled to Pakistan this year to try to receive training from a militant group linked to al-Qaida, and tried to go to Afghanistan and Iraq to fight against US forces there. Kaziu was to be arraigned later Thursday. Prosecutors did not have the name of his attorney.