Then investigators managed to recover the VIN, hidden on the sport utility vehicle's engine block - and thus began a chase that led to the arrest of the would-be bomber 53 hours and 20 minutes after the smoking vehicle was spotted on one of the busiest streets in America.
A Pakistani-born U.S. citizen, Faisal Shahzad, was hauled off a flight to Dubai and arrested late Monday; federal authorities say he has admitted to plotting the attack. He was charged Tuesday with terrorism and attempting to use a weapon of mass destruction.
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"Jack Bauer might have caught him in '24'," said Police Commissioner Raymond Kelly, referring to Fox's popular TV show "24." "But in the real world, 53's not bad."
Court documents unsealed Tuesday show investigators have collected considerable evidence linking Shahzad to the attempted bombing, reports CBS News national security correspondent Bob Orr.
The investigation's clock started ticking at 6:28 p.m. Saturday when a security camera captured images of the dark-colored Pathfinder with tinted windows parked on West 45th Street, in an area lined with Broadway theaters and restaurants.
Six minutes later, a street vendor pointed out the SUV, which had started belching white smoke and making "popping noises," to a police officer on horseback. The officer, Wayne Rhatigan, called in a report of a car fire, flagged down other officers and started evacuating the area.
At 6:40 p.m., firefighters were on the scene. After breaking the car's side and back windows to try to put out the fire, they discovered its sinister contents: three propane tanks, two gallons of gasoline and a load of fertilizer, with fireworks and some cheap alarm clocks as a trigger.
The New York Police Department bomb squad was called in and went to work dismantling the device, defusing it by 11:30 p.m. Times Square, clogged with tourists on a warm evening, would be shut down for 10 hours.
Meanwhile, the NYPD and FBI were pursuing the license plate attached to the back of the SUV. Investigators tracked it to a used auto parts shop in Stratford, Connecticut, waking the owner at 3 a.m. Sunday and discovering the plate was connected to a different vehicle.
Investigators also spoke to the owner of an auto shop in nearby Bridgeport because a sticker on the Pathfinder had indicated the SUV was sold by his dealership. That also led nowhere.
Then at 7:30 a.m. Sunday, Detective John Wright slid underneath the SUV at a Queens lab and discovered the clue that would crack the case - a VIN number stamped on the bottom of the engine block.
That led authorities to a Bridgeport, Connecticut, man and his 19-year-old daughter, Peggy Colas, who had posted ads on eBay and other websites to sell a 1993 Nissan Pathfinder, court papers said.
During questioning on Sunday morning and again Monday, the teenager told investigators she met the man who bought her car at a supermarket parking lot on April 24 and he took the vehicle for a test drive. She was asking $1,800; he offered $500 less. She agreed and he paid her in cash - with 13 crisp $100 bills.
No bill of sale was necessary, she said the buyer told her, and he already had plates. She did not know his name - but she did have a cell number.
That led to a prepaid cell phone activated on April 16 and used to call Colas several times, investigators said. A check of phone records showed it was also used to contact a Pennsylvania fireworks shop.
By 11 a.m. Monday, investigators knew the suspect's name.
Agents later showed Colas a photo array with six photos, including one of Shahzad. Authorities say she picked Shahzad.
Meanwhile, there was more evidence.
A set of keys left in the Pathfinder's ignition turned out to belong to a white Isuzu Trooper that Shazhad left parked at New York's Kennedy airport Monday night, as well as to his apartment in Bridgeport, Connecticut. At a garage at the residence, investigators recovered fireworks and fertilizer, court papers said.
Shahzad was spotted at around 3 p.m. Monday coming out of a store near his home and was tailed by investigators. He was also placed on a no-fly list.
Read criminal complaint against Faisal Shahzad
Authorities planned to arrest him at his apartment that evening, but Shahzad may have gotten spooked by news reports that investigators were seeking a Pakistani suspect in Connecticut, two people familiar with the probe said.
He managed to slip federal surveillance, according to those sources and a law enforcement official. All spoke on condition of anonymity because they were not authorized to speak about the case.
Shahzad headed for Kennedy airport, calling in a reservation for an Emirates flight to Dubai by cell phone while en route, and paying for the ticket in cash before boarding the plane, authorities said.
Emirates officials were unaware he was on the no-fly list because they did not check a Web forum where the latest updates are posted. So it was only when a customs agent assigned to the case spotted Shahzad's name on the flight manifest 30 minutes before takeoff that authorities knew he was on board.
He was belted in to his seat when FBI investigators and NYPD officers entered the jetliner and took him into custody.
The time was 11:45 p.m. - 53 hours and 20 minutes after the Times Square scare began.
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