.Stepped up security following the botched Christmas bombing attempt aboard a jet landing at Detroit does not appear to be causing a major inconvenience for passengers at Philadelphia International Airport today.

Lines were not long at security check ins and there was no visible presence of heavily armed officers.

Passengers said whatever inconvenience they encountered was expected and welcome.

Travelers returning to the United States from overseas yesterday reported extensive searches before they were allowed to board planes and restrictions on their movements as they neared their American destinations, the Associated Press said.

Barbara Porter, 27, and Sebastien Bacle, 28, of South Philadelphia, arrived at Philadelphia this morning after a flight from Canada.

Bacle said passengers for the flight from Ottawa underwent a thorough pat-down and officers searched every carry on bag, which was limited to one per person.

He said that during the last hour of the flight no one was permitted to use an electrical device on the plane.

"It was nothing out of the ordinary," Bacle said.

The Gaydos family - Chris, 43, Vicky, 36, and their sons Nicholas 12, and Kieran, 7 - arrived from Miami to begin a 2 1/2 drive back to their home in Millville, in north-central Pennsylvania.

Chris Gaydos estimated it took an extra 10 minutes to get through security in Miami.

"Personally I don't think it was that much of an inconvenience," he said, adding he underwent a pat-down and a full-body scan.

"It checks your body cavities for any foreign objects," Gaydos said.

"It's nice to know they're doing that," said Vicky Gaydos. "I'd rather land safely. If we had been late for the flight, that might have been different."

Alexana Kubler, 21, of Greenberg, Pa., arrived 9 1/2 hours early for a flight to London and had the west wing of the international terminal to herself.

Kubler, who was headed to a 11-day Penn State theater program, said it was plans to meet a friend - not security - that prompted her early arrival.

"I'm anticipating delays from London back home," she said. "But I'm hoping to get through it as early as I can."

Good advice for anyone catching a flight these days.

Even with the heightened security awareness triggered by the Detroit incident, a glitch at Philadelphia International Airport allowed 64 passengers coming from Cancun to briefly avoid customs inspectors late Sunday.

The passengers were among 133 who arrived about midnight on a USA3000 flight. As the passengers were being routed from the plane to a customs station, some mistakenly entered a doorway that led to the domestic terminal instead.

The doorway had been left open by USA3000 personnel after they used it to take a passenger in wheelchair to an elevator to the custom station, according to Steve Sapp, a spokesman for the U.S. Customs and Border Protection.

Eventually all but three wayward passengers were found and redirected through customs, Sapp said. It was relatively easy, he said, because the flight's checked luggage arrived, as scheduled, at the international terminal. Anyone wanting to retrieve their luggage had to make their way back to customs.

The three who never made it back were a man and his two young children. They had been permitted to leave airport after the children's mother, who was traveling with them, asked she could take the family's luggage through customs while the sleepy children were placed in the family car, Sapp said.

USA3000 could face a fine or other penalty as a result of the incident, Sapp said.