Investigators believe the bicyclist who bombed the Times Square military recruiting station is a local man with ties to chaos-crazed anarchy groups, a high-ranking law-enforcement source said yesterday.
The revelation opened a new avenue after a promising lead connecting the attack to a series of letters shipped to Washington lawmakers' offices crumbled.
• Click here to view photos from the blast.
The official said the entire attack - including the dumping of the bike in a trash bin blocks away from the explosion - seemed well planned because it appeared the suspect scouted out his escape route.
"He seems to be toying with everyone," the official said, speaking on condition of anonymity.
Cops yesterday pored over dozens of surveillance tapes that tracked the bicycle-riding bomber from Times Square, across 43rd Street to Fifth Avenue and finally to Madison Avenue and East 38th Street, where he ditched his wheels.
Police recovered the blue Ross 10-speed in good condition in a trash bin and believe it was the one used in the attack early Thursday.
After the bike was tossed, surveillance footage shows the bomber walking with another person, although it is unclear if he or she was involved.
The FBI ruled out the letter writer - David Karnes of Los Angeles - as having anything to do with the bombing. No one was hurt in the explosion, which shattered windows and twisted the recruiting station's door like a pretzel.
Despite the timing of the arrival of the letters at dozens of Capitol Hill offices boldly claiming "We Did It" with a photo of Karnes standing in front of the recruiting center, officials called it an "unbelievable coincidence."
Sources said Karnes frequently sends politically themed material to Democratic lawmakers, and the ones received Thursday did not contain any threatening messages.
FBI investigators interviewed the man and determined the photo was taken several years ago and made into a holiday-type card bearing the message "Happy New Year. We did it." What he was referring to, the sources said, was the 2006 elections in which the Democrats regained control of Congress.
Investigators also continued to determine whether there is any connection between the bombing and two similar blasts in 2005 and 2007 at the British and Mexican consulates in New York.
The 2007 bombing fell on the one-year anniversary of the death of New York-based anarchist Brad Will, shot while filming a violent demonstration in Mexico.
The 2005 explosion coincided with the re-election of former Prime Minister Tony Blair. Thursday's blast came two weeks short of the fifth anniversary of the US invasion of Iraq.
In the earlier attacks, the bomber used black-powder bombs fashioned out of dummy hand grenades and set off with a lit fuse. While bomb experts were still looking over the evidence, it is believed that a similarly constructed bomb - although packed into a metal ammunition box - was used.
Meanwhile, the mood was defiant at the recruiting center yesterday as officers there tried to get back to business as usual.
"It's just another day. The only difference is I don't have a door," said station commander Sgt. James Latella. "We don't give up."
One potential recruit, Erica Randall, 17, said the attack only spurred on her determination to join the Army.
"It was pointless. I don't know why anyone would do that," she said.