By Daniel Trotta and Svea Herbst-Bayliss
NEW YORK/BOSTON (Reuters) - U.S. authorities searched four locations in the New York City and Boston suburbs in connection with the attempted Times Square bombing, arresting two people on suspected immigration violations, the FBI said on Thursday.
FBI spokesman Richard Kolko said the search warrants were in connection with the failed May 1 bombing but declined to comment on any link between the Boston area arrests and the bomb plot. He said the New York searches took place on Long Island.
A separate FBI statement issued in Boston stressed that there was no known immediate threat to the public.
Pakistani-American Faisal Shahzad was arrested aboard a Dubai-bound jetliner two days after the crude car bomb was found parked in Times Square. He has been charged with attempting to use a weapon of mass destruction and trying to kill and maim people.
Shahzad, 30, who was born in Pakistan and became a U.S. citizen last year, has admitted to the failed plot and to receiving bombmaking training in a Taliban and al Qaeda stronghold in Pakistan, prosecutors said, but he claims to have acted alone.
Investigators are looking at possible links to the Pakistani Taliban and a Kashmiri Islamist group.
The Pakistani Taliban claimed responsibility for the failed bombing attempt. If proven, it would be the group's first act in the United States.
In prepared remarks to the House Judiciary Committee in Washington, Attorney General Eric Holder said U.S. law enforcement authorities were working with their counterparts in Pakistan to find anyone else responsible.
"We will use every resource available to make sure that anyone found responsible, whether they be in the United States or overseas, is held accountable," Holder said, repeating that Americans believe the Pakistani Taliban was responsible.
The Boston searches were at a house in Watertown and a gasoline station in affluent Brookline.
Vincent Lacerra, who lives across the street from the searched home in Watertown, told the Boston Globe he was watching television at about 6 a.m. (11:00 a.m. British time) when he heard a commotion outside and the words, "FBI! Don't move, put your hands up!"
He looked outside to see about 20 agents with guns drawn and pointed at the house, the Globe reported on its website.
Soon afterward, a man was taken from the house and put into an Immigration and Customs Enforcement van.
(Additional reporting by Jeremy Pelofsky in Washington; Writing by Daniel Trotta; Editing by Doina Chiacu)