Extra pat-downs before boarding. No getting up for the last hour of a flight. More bomb-sniffing dogs. Airports worldwide tightened security a day after a passenger tried to light an explosive on a flight into Detroit.

The Transportation Security Administration would not say exactly what it was doing differently. It didn't need to.

Passengers getting off planes from overseas yesterday reported being told they could not get out of their seats for the last hour of flight. Air Canada also said that during the last hour, passengers would not be allowed access to carry-on bags or allowed any items on their laps.

The Transportation Security Administration directive applied to U.S.-bound flights from overseas, according to a TSA official who was not authorized to speak publicly and spoke on condition of anonymity.

The official said passengers traveling internationally could see increased screening at gates and when they check bags, as well as other measures during flight such as stowing carry-ons and personal items before landings.

Flight attendants on at least one domestic flight yesterday, from New York to Tampa, Fla., informed passengers of similar rules. They were told they must remain in their seats and could not have items in their laps, including laptops and pillows.

Passengers on a United Airlines flight from Amsterdam to Washington were not allowed to have anything on their laps during the descent into Dulles International Airport, or to open the overhead bins an hour before landing, said Nehmi Klaassen, 32, who made the trip yesterday.

Klaassen, who lives in Amsterdam, said lines at the airport were "10 times" longer than usual.

Jennifer Allen, 41, of Shelby Township, Mich., encountered tougher security on her way yesterday from Amsterdam to Detroit. Her Northwest Airlines flight was on the same route disrupted Friday by the attempted attack.

"They patted you down really well," said Allen. "It wasn't just a quick rub - it was a slow pat. They went through everything in your bags, went through the pockets in your pants, the pockets of your coat."

Sarabjit Dhillon, 35, of Sterling Heights, Mich., was returning to Detroit from India. Even her three young children got a pat-down.

"They had to open each and every item," she said.

Judith Sluiter, spokeswoman for the Dutch National Coordinator for Counterterrorism, said, "The extra measures apply worldwide on all flights to the U.S. as of now and for an indefinite period."

The big U.S. airlines all declined to talk about the new rules. Southwest Airlines Co. is unaffected because it flies only domestically, spokesman Paul Flaningan said.

The incident on Friday's Northwest flight is a reminder that securing U.S. airports is only part of the solution, said Elaine Dezenski, who until recently was managing director of the Global Security Initiative at Interpol and also used to work for the U.S. Homeland Security Department.

"More and more it's not about what happens in the U.S. airports, it's what's happening outside the U.S. and how the system can or cannot be infiltrated," she said.

At Seattle-Tacoma International Airport, airport police dogs, which are trained to detect explosives, were out yesterday. Airport spokesman Perry Cooper said the extra effort was at the TSA's request.

Passengers flying to the United States from London's Heathrow Airport said they had been notified by text message that they could carry only one piece of hand baggage aboard.

Italy's civil aviation authority, ENAC, said the extra measures were requested by the TSA and were to remain in place initially for 72 hours.

Amsterdam's Schiphol Airport, where Friday's Northwest flight originated, is one of Europe's busiest and transports passengers from Africa and Asia to North America. For about a year, it has been testing full-body scanners that allow security staff to see passengers' outlines and potential weapons beneath their clothes, and it intends to introduce a more complete program next year, said airport spokeswoman Mirjam Snoerwang.

Passengers flying out of Brussels, where the European Union is based, were advised to get to the airport three hours before departure to allow time for a second security check at the boarding gate.

In Sweden, Denmark, and Norway, airport operators said that they would apply tougher security checks on flights destined for the United States, but that they did not plan tighter rules for other flights.

Officials in the Mideast and in India said they were maintaining their current security procedures, which they said were already strict.

Little was different at the airport in Lagos, Nigeria, where suspect Umar Farouk Abdulmutallab's trip originated. Soldiers stared impassively yesterday at those passing into the departure terminal. Others sat and talked among themselves, loaded rifles tossed over their shoulders.

Passengers moved quickly through security, waiting only for immigration officers to examine passports and visas. A battered X-ray machine quickly passed over suitcases and shoes. Federal airport authority spokesman Akin Olukunle said the airport had no bomb-sniffing dogs but was considering getting some.