Air traffic was normal for the most part. But Amtrak was all but shut down between New York and Boston.
"It's going to inconvenience a lot of people," Kathleen Kroll of Langhorne told Action News. "But in the long run it's the only way to maybe get this person.
That was the attitude of some travelers at the Trenton train station, faced with delays after Amtrak suspended service between New York and Boston.
Linda Rowan of Levittown, Pa. was worried about getting to her daughter's home near Boston by tomorrow in time for her grandchild's christening.
"She's got people coming in from Utah and other places so she's concerned about people being able to get in," said Rowan.
"I'm trying to go to Washington DC and the trains coming from Boston are all delayed," said Vince Sirabella of Middletown, N.J. He had been waiting in line for about half an hour.
Amtrak officials say security has been stepped up here since the marathon bombings, and armed officers and dogs were patrolling the station.
Amtrak says there are no current threats here, but are urging travelers to report anything suspicious.
Of course people were talking about the marathon bombers.
"They have led these types of dual lives for 7 years and no one recognized any of these symptoms," said Bill Potts of Yardley, Pa. "That's really dangerous."
"It's kind of shocking, particularly with young kids," said Brett Butler of Amherst, Mass., "trying to explain to them why this is happening."
"We are just down here for the weekend," said Nora Vincent of Winnipeg, Canada. "But we were watching the news in Canada, and we just feel very sorry for everyone."
Meantime, at Philadelphia International Airport, people flying into Philadelphia from Boston described an intense police presence up there.
"SWAT teams going down the middle of the street," said Jeff Riley of Medford, N.J.
"I was stopped at 2 checkpoints and my car was searched," said Mindy Hall of New Hope, Pa. "It's crazy, but they're doing a good job."
"Now we just really want closure," said John Ochsendorf, a professor at MIT.
Ochsendorf was in Philadelphia for business. He was anxious to return home to his wife and two children, who are on lockdown, and his MIT community, now dealing with the loss of 26-year-old patrol officer Sean Collier.
"Last night when the shooting erupted on campus there were very, very tense moments for the MIT community in Cambridge," he said. "Very sad. We lost one of our police officers.
Ochsendorf says he didn't know Collier well, but would see him around campus. He told Action News he is deeply shaken by such a violent death of one of his colleagues.
"We've interacted with him before," said Ochsendorf. "A really good guy, positive guy, just doing his job."