Authorities identified the man as Scott McGann, 32, of New York. He had a ticket on a United Airlines flight that was headed to Chicago, with connecting flights that would have ultimately taken him to Oakland. McGann faces charges including placing a false bomb in a transportation facility and making terroristic threats.

The trouble began shortly after 5 a.m., when McGann checked in for a flight and immediately began attracting attention because of bizarre behavior.

Police received two calls about an apparently intoxicated or suspicious passenger before the man had even reached a security checkpoint, said John Kelly, a spokesman for the Port Authority of New York and New Jersey.

Security officials said he was "just acting crazy," Kelly said.

Authorities detained McGann when he didn't respond to questions. A search of his bag turned up an assemblage of batteries and wires that police thought was intended to look like a bomb, Kelly said.

The terminal was evacuated at around 5:30 a.m. Investigators quickly determined that the device wasn't dangerous, but travelers became quickly inconvenienced as flights were postponed and traffic backed up outside. Passengers didn't get back in to the terminal until close to 9 a.m.

LaGuardia handles about 70 flights per hour, both departures and arrivals.

Roughly a half-dozen United flights were delayed because of the incident at LaGuardia, airline spokesman Rahsaan Johnson said. On the arrest, he said, "We are cooperating with authorities."

Delta Air Lines Inc., the world's biggest airline operator, has a separate terminal from where the incident occurred, so planes continued to arrive and depart. But flights were still disrupted because pilots and flight attendants couldn't make it to the airport because of the traffic backup, airline spokesman Carlos Santos said.

Discount carrier AirTran Airways canceled two flights and delayed about a dozen others due to the incident at LaGuardia, spokesman Christopher White said.

"The planes that go to LaGuardia will be delayed the rest of the day I'm sure," he said.

Among the delayed fliers were 12-year-old Samantha Casady and her 10-year-old brother, Patrick, of Norwich, Conn., who were supposed to fly to Dallas at 7:15 a.m. by themselves to visit relatives.

Their mother, Colleen, said she and her husband were accompanying their children through a long security screening line when there was a commotion "and just a swarm of TSA."

Casady said she later saw a man in handcuffs, surrounded by police.

The family was initially directed to go to another security gate, but it was closed, "and a few minutes later, they evacuated the building," she said.

The evacuation also meant that Irma Quidore, of Denville, N.J., had to delay a trip to Monterrey, Mexico, for a second time with her two daughters, Sofia, 6, and Isabella, 3.

They had originally planned to fly out on Thursday, but a delay that would have forced them to miss a connecting flight prompted them to reschedule their trip for Saturday, Quidore said.

"I guess we're going to make the trip to Mexico, but a little bit late," Sofia said as she pushed her little sister in a stroller toward the terminal.