Faisal Shahzad was arrested at JFK airport late on Monday, as he was about to board a Dubai-bound flight. The 30 year old is suspected of trying to detonate a car bomb in New York's Times Square at the weekend.

Citing official sources, Reuters news agency has reported that the man told investigators that he acted alone and denied any links to radical groups in Pakistan.

Shahzad, who is a native of Karachi, became a US citizen last year. He lived in Connecticut. Some reports suggest he had recently returned from a five-month trip to Pakistan, including Peshawar, close to Islamist strongholds in the tribal areas along the Afghan border.

Full cooperation from Islamabad

Pakistan has promised full cooperation with the US investigation into the suspect. "When an official request comes for that individual, we will cooperate," Interior Minister Rehman Malik told reporters outside parliament.

There have also been reports that the US ambassador to Islamabad, Anne Patterson, held talks with the Pakistani Foreign Minister Shah Mehmood Qureshi on Tuesday on this issue. But no details have been revealed.

Possible links with Taliban?

The US authorities are reportedly also trying to find out whether the suspect might have had contacts with militants in Pakistan or elsewhere.

Earlier the Pakistani Taliban claimed responsibility for the attempted bombing at Times Square. A web video showed its leader Hakimullah Mehsud - until recently believed dead - threatening to attack US cities with suicide bombers. This seems to be Mehsud's first appearance since it was reported that he had been killed in a suspected US drone attack last January.

Experts say if it is confirmed that the person involved in the New York bomb plot had a Pakistani connection, it would increase pressure on Islamabad to step up action against militant networks in the country.

A policeman was alerted to a parked Nissan Pathfinder in Times Square on Saturday after people noticed smoke coming from it. Police said the vehicle was loaded with petrol, propane gas tanks, fireworks and fertilizer. The authorities said the car bomb could have caused significant casualties, had it exploded.

du/Reuters/AFP/AP

Editor: Grahame Lucas