New York officials said on Sunday police had arrested a man trying to build a pipe bomb with instructions from an al Qaeda magazine which he planned to use against U.S. soldiers returning from Iraq and Afghanistan.
The suspect - identified as Jose Pimentel, 27 - was charged with three terrorism-related counts and two other counts, court documents said.
Beyond soldiers, his intended targets were allegedly police officers and post offices, Police Commissioner Raymond Kelly said at a joint news conference with New York Mayor Michael Bloomberg and District Attorney Cyrus Vance, the chief prosecutor for Manhattan.
Pimentel had been under surveillance since May 2009 and was a lone wolf who got instructions on building a pipe bomb from Inspire magazine, published by al Qaeda in the Arabian Peninsula, Kelly said.
Pimentel was arrested on Saturday, Bloomberg said.
In an interview with New York police, Pimentel admitted he took active steps to build the bomb, including shaving the match heads and drilling holes in the pipes and was one hour away from completing it, the court documents said.
Since the September 11 attacks by al Qaeda militants in 2001, New York City has considered itself a prime target and has developed extensive intelligence and counterterrorism divisions within the New York Police Department.
New Yorkers have grown accustomed to heightened security and regular announcements that authorities have foiled plots to attack the city.
Most planned attacks - such as that linked to the September 2009 arrest of Najibullah Zazi, an Afghan-born man who was a permanent U.S. resident living in Colorado who plotted a suicide bomb attack on the New York subway system - were aspirational. Zazi later pleaded guilty.
But some, such as the failed May 2010 attempt to bomb the city's Times Square, were closer to being carried out.
In that case, a Pakistani-born U.S. citizen, Faisal Shahzad, drove a sport utility vehicle packed with a crude bomb into the heart of Times Square on a crowded Saturday evening. The bomb failed to go off and was discovered by passersby.