Pakistani-American Faisal Shahzad, the Times Square bomb suspect, fears for his life after spilling the beans to investigators, but is dying to know why his homemade explosive never exploded in the crowded area of New York city.
A law enforcement official told the New York Post that Shahzad had expressed surprise that his homemade bomb didn't detonate -- and begged them to explain where he went wrong.
Experts have noted that the type of fireworks used in the device were not potent enough to set off a chain reaction necessary to ignite the containers of propane, gasoline and fertiliser, and also the fertiliser used was non-explosive.
The source did not say whether the investigators decided to tell Shahzad what went wrong with his plan. On May 1, Shahzad tried to blow up Times Square by leaving a car packed with explosives in the popular tourist site.
The 30-year-old Pakistani American was apprehended 53 hours later at John F Kennedy airport trying to escape to Dubai. He is believed to have been working in collusion with the Pakistan-Taliban.
If the Times Square bombing was successful, Shahzad planned to attack four other targets--Rockefeller Center, a Grand Central Terminal, the World Financial Center and the Connecticut headquarters of defense contractor Sikorsky.
The father of two worked as a financial analyst in Connecticut where he lived with his wife. But his personal and professional life began to unravel last year during the financial crisis.
In two emails, the terror suspect has expressed frustration with the state of the Muslim world.
Meanwhile, Fox 5 News reported that Shahzad claimed to have left his wife, Huma Mian, because she had become too modernised. The 28-year-old American citizen grew up in Colorado.
While appearing in a Manhattan federal court for the first time this week, Shahzad did not speak much during his arraignment proceedings that lasted about 15 minutes. He said "yes" when asked to confirm the accuracy of a financial statement.
Having waived his arraignments rights for more than two weeks, Shahzad has been cooperating with the authorities.
On Tuesday, he received several charges including attempted terrorism and attempted use of a WMD. If convicted, he could be in prison for life.
Three other Pakistani men in the U.S. were arrested last week on suspicion of funneling money to Shahzad but they do not face criminal charges in connection with the foiled terror plot.