Denver: Counterterrorism officials are warning US mass transit systems to step up patrols because of fears an Afghanistan-born immigrant under arrest in Colorado may have been plotting with others to detonate backpack bombs aboard New York City trains.
Investigators said Najibullah Zazi, a 24-year-old shuttle van driver at the Denver airport, played a direct role in a terror plot that unraveled during a trip to New York City around the anniversary of the September 11, 2001 attacks.
He made his first court appearance on Monday and remained behind bars.
In a bulletin, officials recommended that transit systems conduct random sweeps at terminals and stations and that law enforcement make random patrols and board some trains and buses.
Meanwhile, the investigation into Zazi's role and how many others may be involved was ongoing.
The FBI said in a statement that "several individuals in the United States, Pakistan and elsewhere" were also being investigated.
Backpacks and cell phones were seized last week from apartments in Queens where Zazi visited.
Investigators said they found notes on bomb-making instructions that appear to match Zazi's handwriting, and discovered his fingerprints on batteries and a scale that could be used to make explosives.
He also made a trip to Pakistan last year in which he received Al Qaida explosives and weapons training, the government said.
