An al-Qaida sympathizer was on the verge of putting his terror plans into action when New York City police swooped in to arrest him over the weekend, WNBC investigative reporter Jonathan Dienst told the TODAY show on Monday.
Jose Pimentel that he had been about one hour away from completing a test bomb when he was arrested Saturday, .
Pimentel was accused of plotting to bomb police and post offices in New York City as well as U.S. troops returning home.
Mayor Michael Bloomberg announced at a news conference Sunday the arrest of Pimentel, "a 27-year-old al-Qaida sympathizer" who the mayor said was motivated by terrorist propaganda and resentment of U.S. troops in Afghanistan and Iraq.
Police Commissioner Raymond Kelly said police had to move quickly to arrest Pimentel on Saturday because he was ready to carry out his plan.
"We had to act quickly yesterday because he was in fact putting this bomb together. He was drilling holes and it would have been not appropriate for us to let him walk out the door with that bomb," Kelly said.
The police commissioner said Pimentel was energized and motivated to carry out his plan by the Sept. 30 killing of al-Qaida's U.S.-born cleric Anwar al-Awlaki.
"He decided to build the bomb August of this year, but clearly he jacked up his speed after the elimination of al-Awlaki," Kelly said.
But federal authorities on Monday said they declined to pursue the case against Pimentel because they believed he was mentally unstable and incapable of pulling off the alleged plot, two law enforcement officials said Monday.
New York Police Department investigators sought to get the FBI involved at least twice as their undercover investigation of Jose Pimentel unfolded, the officials said. Both times, the FBI concluded that he wasn't a serious threat, they said.
The FBI concluded that 27-year-old Pimentel "didn't have the predisposition or the ability to do anything on his own," one of the officials said.
The officials were not authorized to speak about the case and spoke on condition of anonymity. The FBI's New York office declined to comment on Monday. New York City authorities said that the FBI was involved in the case, but did not specifically say they declined to pursue the charges.
"We just believed that we couldn't let it go any further. We had to act," Kelly said.
Pimentel's mother spoke to reporters outside her upper Manhattan home the day after her son was arraigned in state court on terrorism-related charges.
"I didn't raise my son in that way," Carmen Sosa said. "I feel bad about this situation."
She also praised the New York Police Department, saying, "I think they handled it well."
Ten years after 9/11, New York remains a prime terrorism target. Bloomberg said at least 13 terrorist plots have targeted the city since the Sept. 11 attacks. No attack has been successful. Pakistani immigrant Faisal Shahzad is serving a life sentence for trying to detonate a car bomb in Times Square in May 2010.
Pimentel, a U.S. citizen originally from the Dominican Republic, Pimentel was "plotting to bomb police patrol cars and also postal facilities as well as targeted members of our armed services returning from abroad," Bloomberg said Sunday.
A source told WNBC's Shimon Prokupecz that the suspect had been under police surveillance since 2009.
Authorities have no evidence that Pimentel was working with anyone else, the mayor said.
"He appears to be a total lone wolf," the mayor said. "He was not part of a larger conspiracy emanating from abroad."
Instead, Bloomberg said, Pimentel represents the type of threat FBI Director Robert Mueller has warned about as U.S. forces erode the ability of terrorists to carry out large scale attacks.
Pimentel, also known as Muhammad Yusuf, is accused of having an explosive substance Saturday when he was arrested that he planned to use against others and property to terrorize the public.
The charges accuse him of conspiracy going back at least to October 2010, and include first-degree criminal possession of a weapon as a crime of terrorism, and soliciting support for a terrorist act. He was ordered held without bail at his arraignment later Sunday.
"This is just another example of New York City because we are an iconic city ... this is a city that people would want to take away our freedoms gravitate to and focus on," Bloomberg said.
Kelly said a confidential informant had numerous conversations with Pimentel on Sept. 7 in which he expressed interest in building small bombs and targeting banks, government and police buildings.
Pimentel confessed to building bombs, and waging war against the United States, and aspirations to assassinate politicians and government workers, according to the complaint, WNBC reported. In a video statement to police, Pimentel said he was one hour away from completing the bomb.
Pimentel also posted on his website trueislam1.com and on blogs his support of al-Qaida and belief in jihad, and promoted an online magazine article that described in detail how to make a bomb, Kelly said.
Among his Internet postings, the commissioner said, was an article that states: "People have to understand that America and its allies are all legitimate targets in warfare."
The New York Police Department's Intelligence Division was involved in the arrest. Kelly said Pimentel spent most of his years in Manhattan and lived about five years in Schenectady. He said police in Albany tipped New York City police off to Pimentel's activities.
Asked why federal authorities were not involved in the case, Manhattan District Attorney Cyrus R. Vance Jr. said there was communication with them but his office felt that given the timeline "it was appropriate to proceed under state charges."
About 1,000 of the city's roughly 35,000 officers are assigned each day to counterterrorism operations. The NYPD also sends officers overseas to report on how other cities deal with terrorism. Through federal grants and city funding, the NYPD has spent millions of dollars on technology to outfit the department with the latest tools -- from portable radiation detectors to the network of hundreds of cameras that can track suspicious activity.