'Heightened Security' at Logan Airport After Boston Marathon Bombings

April 16, 2013— -- The bombings that killed three and injured 176 others at the Boston Marathon Monday have put the city – and travelers – on high alert.

Massport, the state agency that manages Logan Airport, said Tuesday that there was "heightened security on roadways, in terminals and on the airfield."

PHOTOS: Terror at the Boston Marathon

Heightened security at airports generally leads to longer lines. JetBlue, which has a hub at Logan, said that while flights were moving well, customers may want to allow more time to go through security.

Around the country, flights are departing on time, except in Boston, where the flight tracking website FlightAwaredelays reported 30 to 45 minute delays on Boston departures Tuesday morning. There was a brief ground stop at Logan on Monday in the hours after the bombings, but "Boston Logan International Airport remains open, connecting Massachusetts and New England to the world," Massport CEO Thomas P. Glynn said in a statement Tuesday morning.

At least one flight was delayed at an airline crew's request. United Airlines said Flight 636 going from Boston to Chicago was delayed because the crew members requested that travelers and their bags be rescreened before departure. The aircraft was swept and cleared for takeoff.

And a US Airways flight arriving in Boston from Philadelphia was parked in a remote airfield "out of an abundance of caution" while a bag on board was examined. "The passengers were bused to the terminal, the baggage was deemed harmless, and the flight taxied to the gate," the airport said on its Facebook page.

Those taking public transportation to and from Logan should expect additional police presence, "including random searches of packages, bags and backpacks," said Massachusetts Gov. Deval Patrick.

Travelers with plans to visit Boston who wish to change their trip dates can take advantage of flexible rebooking policies issued by several airlines, including American, AirTran, Delta, JetBlue, Southwest, United Airlines, US Airways and Virgin America, in the wake of the marathon bombings.

Such policies, usually reserved for severe weather, vary by carrier, but they generally allow passengers who hold tickets for travel through Boston to take their trip at a later date without penalty. Most policies require travel to begin no later than April 20, but United is allowing one year from the date of ticket issue to travel.

The price of changing a flight is usually about $150.