Federal authorities are warning law enforcement personnel of a possible terror plot against the New York City subway system during the holiday season.
Faced with a fresh warning of a possible terror attack on the city's mass transit system, commuters and out-of-towners responded Wednesday with a mix of resignation, bravado and something like a collective shrug.
"My whole life is riding the subway," said Beth Maderal, 26, as she waited with her mother on a Brooklyn subway platform. "If it's open, I am going to ride it."
Earlier Wednesday, federal authorities warned police of an unsubstantiated report that al-Qaida operatives discussed an attack on New York's subway system or rail lines like Amtrak and the Long Island Rail Road.
Such intelligence alerts have been commonplace since the Sept. 11 terror attacks, and city officials Wednesday seemed to play down the warning. A spokesman for Mayor Michael Bloomberg said he had no plans to comment.
NBC New York has confirmed that the FBI released an internal memo saying the agency has received a "plausible but unsubstantiated" report that al-Qaida terrorists in late September may have discussed attacking the subway system.
According to the memo, terrorists have discussed targeting transit systems in and around New York City.
These discussions reportedly involved the use of suicide bombers or explosives placed on subway/passenger rail systems," according to the document.
"We have no specific details to confirm that this plot has developed beyond aspirational planning, but we are issuing this warning out of concern that such an attack could possibly be conducted during the forthcoming holiday season," states the warning, which is dated Tuesday.
The source of the notice to New York about trains and subways is a man detained in Pakistan who was questioned by the FBI on a range of subjects, U.S. officials told NBC News.
During the course of the questioning, he volunteered that he heard discussions about a month ago among al Qaeda operatives about their desire to stage bomb attacks on New York trains and subways around the holidays.
Among those that he said he had overheard, authorities said, were people who claimed to have some familiarly with Long Island, presumably from having been there at some point.
The source was not the usual Internet chatter or a walk-in to an embassy.
However, NBC News has learned that has not been enough time to check out the man's story.
The FBI and Homeland Security felt that they had to notify NYPD immediately. They are not sure whether the man really heard what he claimed and, if so, whether the people he heard talking were merely describing their desires or talking about something more concrete.
While federal agencies regularly issue all sorts of advisory warnings, the language of this one is particularly blunt.
The Big Apple's tightly packed passenger trains and subway cars have long been a source of concern for cops -- and a tempting target for would-be terrorists -- but there is often disagreement as to how seriously authorities should take specific intelligence reports.
NYPD spokesman Paul Browne said additional resources were being deployed in the mass transit system in an "abundance of caution," a common response when police receive new information about a threat.
The Metropolitan Transportation Authority, which oversees the city's 468 stations and 6,480 subway cars, released a statement saying there was "no reason to be alarmed."
Commuters riding the rails said they were used to warnings of possible terror attacks but could not afford to change their routine everytime someone sounds an alarm.
"I could get hit by a truck, too, so it doesn't bother me," said 57-year-old Paul Greenwald, a phone technician from Long Island, as he bought a subway pass at the Pennsylvania Station transit hub. "I gotta live my life."
Edward Lipinsky, 60, of Brooklyn, also said he wasn't afraid.
"Maybe if they had more specifics I would have fear, but right now just hearing about a terror warning is not enough to send chills down my spine," he said as he exited the subway station at Rockefeller Center.
The police and MTA have tried to bolster security in recent years.
Uniformed police are a common sight on Manhattan subway platforms, and officers occasionally set up checkpoints to inspect travelers' bags.
There are signs everywhere warning passengers to be on the lookout for unattended packages. At major transport hubs, passengers can sometimes see police or soldiers carrying rifles.
Those precautions, and others, have made some people feel somewhat safer.
"I'm sure the government is doing a lot of security and you can see a lot of police at the station," one subway rider, Alvaro Castro, said Wednesday.
Maderal, the dance and yoga instructor interviewed at a Brooklyn subway stop with her mother, says the chatter about terrorists doesn't panic her. "I wasn't here during Sept. 11 so I don't come from that sense of insecurity," she said.
Her mother, Elaine Maderal, who was visiting from Detroit, said she worries about her two daughters living in Brooklyn. She'll be a "little more careful" in the wake of the terror threat but said she was something of a fatalist after a tree fell on her house.
"It's one more example that we're not in control," the mother said.