A man was arrested late Monday night in connection with the failed Times Square bombing, administration officials said. The suspect, Faisal Shahzad, a 30-year-old U.S. citizen from Pakistan, allegedly purchased the sport utility vehicle that authorities found packed with explosives in New York on Saturday night.

He was arrested by Customs and Border Patrol agents at JFK International Airport as he tried to board a flight to Dubai. Authorities became aware of his identity Monday afternoon.

An FBI-led Joint Terrorism Task Force had taken over the investigation Monday amid growing indications of a possible international connection, U.S. officials and law enforcement sources said.

Shahzad, who lived in Connecticut, is believed to have used cash to purchase the Nissan Pathfinder that was set ablaze but failed to detonate Saturday night on a tourist-crowded block in Midtown Manhattan.

Investigators and agents also were scouring international phone records showing calls "between some of the people who might be associated with this and folks overseas," according to a U.S. official who has discussed the case with intelligence officers. Investigators uncovered evidence -- a piece of paper, fingerprints or possibly both -- that also indicates international ties, according to a federal official briefed on the investigation. The material points to "an individual who causes concern to [investigators], who has overseas connections, and they are looking for him," the official said.

An overseas angle does not necessarily mean that the incident was planned or financed by al-Qaeda or another organized group, investigators said. "Think smaller," said one senior law enforcement official, who spoke on the condition of anonymity because the investigation is ongoing.

Even as investigators emphasized that the probe is in its early stages and little is definitively known, they pursued what Obama administration officials characterized as a flood of new leads, both foreign and domestic. The Pathfinder's registered owner, for example, told investigators that he sold it several weeks ago to a stranger, in a cash transaction through Craigslist.

On a day of fast-moving developments from Manhattan to Washington, President Obama was repeatedly briefed on what a senior administration official called "a very active investigation.'' Attorney General Eric H. Holder Jr. said in the morning that it was too early to designate the failed bombing as an attempted terrorist incident. By afternoon, White House spokesman Robert Gibbs was calling it just that.

"I would say that was intended to terrorize, and I would say that whomever did that would be categorized as a terrorist," Gibbs said, sharpening the administration's tone.

Differences also emerged over the significance of a surveillance video that caught a man in his 40s changing his shirt in an alley and looking over his shoulder near where the Pathfinder was parked. New York City police officials had characterized the man as acting suspiciously, but multiple federal law enforcement officials said he may not be the focus of the investigation.

"It looks like he was just taking off his shirt because he was hot," said one law enforcement official. Investigators were seeking to find another person captured on video running north on Broadway away from the area where the smoking sport-utility vehicle caused an evacuation of Times Square on a crowded weekend night.

Police said the bomb would have created a fireball that likely would have killed or wounded many people, making it the most serious bombing attempt in the United States since the Christmas Day attack aboard a commercial flight bound for Detroit.