One of the men, identified as Tauseef, was a friend of Faisal Shahzad, the American citizen of Pakistani origin who is in custody in the United States over the failed attack, one official said. He was arrested in the southern city of Karachi, said the official, who like all Pakistani spies refused to be named in the media.
Another official said several people had been taken into custody in Karachi since the failed attack Saturday. Some media reports described them as relatives of Shahzad.
According to CBS News' Maria Usman, four to eight people are being held after a series of law enforcement raids.
Officials didn't say when the detentions had taken place. They said no charges had been filed.
Shahzad was on board a Dubai-bound flight that was taxiing away from the gate at New York's Kennedy Airport late Monday when the plane was stopped and FBI agents and New York Police Department detectives took him into custody, law enforcement officials said.
U.S. officials have said the 30-year-old had recently returned from a five-month stay in Pakistan, raising speculation he may have been in contact with al Qaeda or Taliban groups in the South Asian country.
Pakistani Interior Minister Rehman Malik said initial information showed Shahzad and his family came from the Pabbi region of northwest Pakistan, but that Shahzad had a Karachi identity card.
"We have to see whether it was an individual act or if it was a collective kind of act," he said.
Several Pakistani officials said U.S. authorities had not made a formal request for the country to help in the probe.
Two security officials in the northwest said Shahzad and his family came from the village of Mohib Bandar in Pabbi, but moved to the North Nazimabad district of Karachi several years ago. They said he was a graduate of an engineering college and the son of a senior Pakistani air force officer.
But a Shahzad family member in the region told a local journalist that the officials were mistaken and that the family had nothing to do with the suspect in the United States. Faisal and Shahzad are very common names in Pakistan.
One local television report said Shahzad spent time on his recent trip to Pakistan in Karachi and in the northwestern city of Peshawar. Peshawar is a gateway for foreigners seeking to travel into the nearby tribal regions where militant groups have long had sanctuaries.
Shahzad is suspected of driving a bomb-laden vehicle into Times Square last Saturday and parking it on a street lined with restaurants and Broadway theaters. He was expected in court to face charges later Tuesday.
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