Indications of the Pakistani Taliban's role in the failed New York car bombing are growing as they question the main suspect in the incident, U. S. officials have said.

According to the reports, Faisal Shahzad, 30, arrested Monday just prior to his Emirates flight to Dubai was to take off from New York, Wednesday waived his right to a speedy arraignment, which The New York Times said was an indication of his cooperation with authorities.

There are "no smoking guns yet" about the Taliban's involvement, but others spoke of strong indications that Shahzad knew some Taliban members who may have helped train him, a senior official in the administration of U. S. President Barack Obama told the Times.

It was further reported that the Connecticut resident is originally from Pakistan and became a naturalized U. S. citizen. Pakistani media reports have said he is the son of a retired air vice marshal and that he and his wife have two children.

Shahzad's interrogation has provided evidence the Pakistani Taliban trained him months prior to Saturday's attempted attack at New York's Times Square, U. S. officials told the Times.

Shahzad also reportedly discussed his contacts with the Taliban, a group that this week sought to show through videos its leader Hakimullah Mehsud was not killed as originally believed in a U. S. drone strike in January. Mehsud's group claimed responsibility for the Times Square incident, the officials have said.

One question that remains unanswered is the source of the cash Shahzad used to buy the SUV used in the attempted bombing and the ticket for his flight to Dubai.

One official told the Times, "Somebody's financially sponsoring him, and that's the link we're pursuing. And that would take you on the logic train back to Pak-Taliban authorizations." (With Inputs from Agencies)