04/15/2013 08:23 pm ET

Boston Bombings Feed Anxiety Over Terrorism In Major Cities Nationwide

NEW YORK -- Nancy Dawson paused briefly from her quick-paced commuter's walk to consider the words scrolling across a news ticker on the side of a building in Manhattan's Times Square. She had heard the news from a colleague just a few minutes before: Bombs had ripped through a crowd at the Boston Marathon on Monday, killing at least two and injuring scores more.

As a lifelong resident of a city that has been the target of multiple terrorist attacks, Dawson said she had a good idea what Bostonians must be feeling Monday afternoon: angry and frightened, for sure, and also deeply sad.

"I hurt for them," she said. "Every time something like this happens I remember 9/11, and get upset all over again."

As of 5 p.m. Monday afternoon, more than 100 people were recorded injured and two dead in the blasts, which occurred near the finish line of one of the nation's most prestigious road races, according to the Boston Globe. A fire broke out around the same time at the JFK Library, but authorities were unsure the incidents were linked.

The blasts downtown in Copley Square occurred at about 2:45 p.m, according to CNN. Videos and still photos posted on social media in the immediate aftermath of the bombings showed some racegoers fleeing in panic, while security officers and other attendees scrambled to pull back shredded security fences, revealing blood-stained sidewalks.

Far beyond Boston, in communities where terrorist attacks are part of recent memory, emergency responders scrambled in now familiar drills meant to reassure residents and ward off any possible would-be copycats or collaborators.

In New York, the site of terrorist attacks in 1993 and 2001 -- as well as a failed car-bomb attack in 2010 -- police "stepped up security" at hotels and other prominent locations, according to New York Police Department Deputy Commissioner Paul Browne.

At rush hour in Times Square on Monday evening, however, there wasn't much sign of the increased police presence. Half a dozen or so police vans had parked along 42nd street, near the Port Authority Bus Terminal. But rather than patrolling, most of the officers on hand stayed inside the vans, some talking on cell phones.

At one point, a line of police cars with lights flashing drove by, but did not stop. Two police officers standing near the police station on a sidewalk corner nearby said they could not discuss whether there was a heightened police presence, or whether they were taking additional security measures. As a reporter watched, one of the officers asked a man dressed up in a worn Spiderman costume to remove a bag he had placed a few feet away. Spiderman nodded, then returned to taking a photo with a tourist.

To the casual observer, it could have been any other evening communte. Some of those who stopped to talk had not heard about the explosions. Others, like Thomas Getta, of Ridgewood, N.J., had already formed theories about what had happened.

"What's today?" Getta asked. "It's tax day. It's April 15th. I guarantee you someone has an axe to grind."

Johanna Beilschmidt, visiting with her boyfriend from Germany, said she was not worried. "We know there is always a risk in everything we do," she said. Then she asked directions to Little Italy.

Elsewhere in Manhattan, last-minute tax filers queued up in long lines at the main branch of the New York City post office.

It's tragic, it's horrible, but how do you really react to that?," said Lisa Pascal, a Queens resident who said her sister had called her a few hours earlier to break the news of the attack. "I was actually very concerned coming into the city to mail my taxes, having to take public transit. But I'm more scared of messing with the IRS."

Officials in Washington, D.C., and Chicago said they were stepping up security on public transit systems.

Sam Gardner, a columnist for Fox Sports who travels regularly between New York and Boston, boarded an Acela Express train to Boston just after the bombing occurred. He told The Huffington Post that the conductor made several announcements, saying the train would arrive as scheduled into Back Bay and South Station. Passengers who wished to return to New York were given the option to disembark in New Haven and board a train back to New York.

"I guess everyone is a little more tense," Gardner said. "But it doesn't seem all that different now than most trips."

In a statement, Amtrak said security will be increased and officers will be held over, but it "will continue to operate normally."

As of Monday evening, there was no immediate word as to who planted the bombs.

"We still do not know who did this or why," President Obama said in a quickly-arranged press conference at the White House. "But make no mistake, we will get to the bottom of this, and we will find out who did this. We'll find out why they did this."

Tim Stenovec and Eleazar David Melendez contributed to this report.