British Airways on Thursday canceled the same London-to-Washington flight that had been isolated and boarded by U.S. authorities upon arrival the day before, an airline spokesman said.

A spokeswoman for the British Department of Transport said she was unable to comment on matters of security or whether the flight's grounding was the result of a specific threat.

"We had some information about this flight," a Department of Homeland Security (search) official told Fox News. "We shared it with the British government. And the decision was made to cancel it."

BA 223 was kept on the tarmac for several hours shortly after landing at Washington Dulles International Airport (search) Wednesday night. The airline spokesman, speaking on condition of anonymity, said U.S. authorities questioned all crew members and 247 passengers on board

He added that Thursday's cancellation had been made following security advice from the British government, and that alternative travel arrangements had been made for the 180 passengers, who had been scheduled to leave London's Heathrow airport at 10:05 a.m.

Neither of the airline's other two London-to-Washington daily flights were canceled.

Wednesday's flight was isolated shortly after it landed in Washington and at least some of its 247 passengers questioned after a 3-hour wait.

Homeland Security spokeswoman Rachel Sunbarger said intelligence led the agencies to detain the flight, but an FBI official, speaking on condition of anonymity, told The Associated Press the incident did not involve terrorism.

But a national security official said Thursday that authorities had been acting on intelligence information, not just suspicious passenger names, when they boarded the jet.

"We had concerns with individuals on the flight, but threat-reporting information led us to make the decision to have the flight escorted," a national security official said, speaking only on condition of anonymity.

"It was fact-related," the official said, and not just connected to the passenger list the United States now receives from airlines flying to the United States.

He said the long delay in questioning those aboard was caused in part by weapons screening of passengers, and partly because authorities waited for some law enforcement specialists to arrive.

Transportation Security Administration (searchspokeswoman Jennifer Marty said passengers aboard Flight 223 were questioned aboard the plane, which landed at 7:06 p.m. EST. Officials began allowing passengers off the plane around 10:30 p.m.

Sunbarger said the baggage on board the flight underwent additional screening.

The plane was kept several hundred feet from the terminal during the questioning.

Passenger David Litwick told WJLA-TV in Washington that he and his wife were not questioned, but at least one other passenger was. Litwick said four FBI agents spoke to a woman who appeared to be from the Middle East, repeatedly asking her why she was not traveling with her husband.

Earlier this week, a scheduled U.S.-bound flight from Mexico was canceled because of security concerns.

"The government of Mexico made the decision to cancel Aeromexico Flight 490 after the U.S. government shared threat information with the Mexican government," Department of Homeland Security spokesman Brian Roehrkasse said.

Previous reports said the plane turned around in midair, but Roehrkasse and Mexican officials said it never took off. Roehrkasse denied that the U.S. government told Mexico it would refuse the plane landing rights.

However Agustin Gutierrez, Mexico's presidential spokesman, said the flight was canceled after United States authorities said they would refuse to allow it to land. He also said Mexico did not receive convincing information for the cancellation.

"The question is what threat?" Gutierrez said. "This question must be answered by Homeland Security. If we are going to have a good climate of cooperation, the least that we can hope for are reasons."

Mexican officials found no evidence of a threat on the flight, Gutierrez said.

The threat of terrorism also prompted the closure Tuesday night and Wednesday of the oil tanker terminal in Valdez, Alaska.

Tankers load Prudhoe Bay (search) oil destined for the Lower 48 states at Valdez, the end of the 800-mile pipeline, which carries 17 percent of the nation's domestic oil supply.

Last week, security was strengthened in the Prince William Sound community after U.S. officials said Al Qaeda operatives could target remote sites such as oil facilities in Alaska. Officials also said then they could not corroborate a report about an Al Qaeda threat against the Valdez oil terminal.

The New York Times reported Wednesday that there have been five or six recent instances of security officials meeting planes and doing "reverse screenings" like the one in Dulles, interviewing passengers and searching them for explosives, weapons and other contraband.

It also said there was an instance several days ago in which a flight headed for the United States from an unidentified Latin American country was grounded on the runway for several hours before being allowed to take off after United States officials told the air carrier they were not satisfied that passengers had been adequately screened initially.

The New York Times also reported that the United States had reached an agreement with a French delegation under which the French will turn over passenger lists for any at-risk flight at least one hour before takeoff, rather than waiting until the flight is in the air, as is now done.

Several Air France flights between Paris and Los Angeles were canceled Dec. 24 because of terrorism concerns.

Fox News' Mike Emanuel and the Associated Press contributed to this report.