Two Afghans accused of making false statements in a counter-terrorism investigation were ordered held in federal custody on Monday until hearings later this week.
Ahmad Wais Afzali, an imam at a mosque in the borough (district) of Queens, was ordered held without bail by a New York federal court, on a charge of making false statements in a counter-terrorism investigation. He faces a bail hearing on Thursday.
Two other men allegedly involved - Najibullah Zazi, and his father, U.S. citizen Mohammed Wali Zazi, were arrested on Saturday in Denver. Both are being held in Colorado pending a hearing on Thursday.
Federal authorities say the younger Zazi received al-Qaida training and had bomb-making instructions on his computer. He has denied being involved in a terror plot.
Zsazi's father is accused of lying when he told authorities he did not know Afzali.
The Federal Bureau of Investigation says it recorded a conversation between the two men. The FBI also says it found backpacks and possible bomb-making components in a New York apartment where the younger Zazi stayed on September 10.
Experts have warned about the possible use of backpack bombs on the New York City subway system, similar to the ones used by al-Qaida terrorists on a commuter train in Spain in 2004 and on three London subway trains and a bus in 2005.
Federal officials are reminding law enforcement agencies across the country that rail and transit systems can be vulnerable to terrorist attacks.