It began as a seemingly offhand remark by the president of Bolivia, who suggested during a visit to Moscow that he might be happy to host Edward J. Snowden, the fugitive former security contractor who is desperate to find asylum. It escalated into a major diplomatic scramble in which the Bolivian president's plane was rerouted on Tuesday, apparently because of suspicions that Mr. Snowden was aboard.
By day's end, outraged Bolivian officials, insisting that Mr. Snowden was not on the plane, were accusing France and Portugal of acting under American pressure to rescind permission for President Evo Morales's plane to traverse their airspace on the way back to Bolivia. Low on fuel, the plane's crew won permission to land in Vienna.
"They say it was due to technical issues, but after getting explanations from some authorities we found that there appeared to be some unfounded suspicions that Mr. Snowden was on the plane," the Bolivian foreign minister, David Choquehuanca, told reporters after the plane touched down in Vienna, where Mr. Morales was spending the night.
"We don't know who invented this big lie," the foreign minister said at a news conference in La Paz, Bolivia. "We want to express our displeasure because this has put the president's life at risk."
Rubén Saavedra, the defense minister, who was on the plane with Mr. Morales, accused the Obama administration of being behind the action by France and Portugal, calling it "an attitude of sabotage and a plot by the government of the United States."
There was no immediate response by officials in Paris, Lisbon or Washington.
"We were in flight; it was completely unexpected," Mr. Saavedra said on the Telesur cable network. "The president was very angry."
Speaking by phone with Telesur, Mr. Saavedra said that Mr. Snowden was not on the plane. Later, Reuters cited an unidentified Austrian Foreign Ministry official as saying the same thing.
Bolivian officials said they were working on a new flight plan to allow Mr. Morales to fly home. But in a possible sign of further suspicion about the passenger manifest, Mr. Saavedra said that Italy had also refused to give permission for the plane to fly over its airspace. Later he said that France and Portugal had reversed course and offered to allow the plane to fly through their airspace after all.
On Monday, Mr. Morales, who was attending an energy conference in Moscow, was asked in an interview on the Russia Today television network if he would consider giving asylum to Mr. Snowden, 30, who has been holed up at Moscow's Sheremetyevo Airport for more than a week, his passport revoked by the United States.
"Yes, why not?" Mr. Morales responded. "Of course, Bolivia is ready to take in people who denounce -- I don't know if this is espionage or monitoring. We are here."
He said, though, that Bolivia had not received a request from Mr. Snowden, despite news reports to the contrary.
It was already clear by then that the Moscow conference had been overshadowed by the drama of Mr. Snowden and his disclosures about American intelligence programs, which have deeply embarrassed the Obama administration.
President Nicolás Maduro of Venezuela, who was also at the conference, had suggested he might offer Mr. Snowden asylum but did not plan to fly him to Venezuela.
But Mr. Morales's remarks appeared to open the door. At least that was the way they were interpreted.
The problems began even before Mr. Morales left Moscow, Mr. Choquehuanca said. On Monday, Portugal, without explanation, had withdrawn permission for Mr. Morales's plane to stop in Lisbon to refuel, the foreign minister said. That required Bolivian officials to get permission from Spain to refuel in the Canary Islands.
The next day, after taking off from Moscow, Mr. Morales's plane was just minutes from entering French airspace, according to Mr. Saavedra, when the French authorities informed the pilot that the plane could not fly over France.
There was also plenty of confusion in Moscow over how Mr. Snowden could possibly have left undetected on a government aircraft.
Government planes carrying foreign officials to diplomatic meetings in Moscow typically arrive and depart from Vnukovo Airport, which is also the main airfield used by the Russian government, rather than from Sheremetyevo, where Mr. Snowden arrived from Hong Kong on June 23 hours after American officials had sought his extradition there.
The speculation that Mr. Snowden would hitch a ride on a government jet was discounted by the fact that the plane would have to first make a quick flight from one Moscow airport to the other.
In an interview with the television station Russia Today, Mr. Maduro said he would consider any request by Mr. Snowden. Then, ending the interview with a dash of humor, he said, "It's time for me to go; Snowden is waiting for me."
Rick Gladstone reported from New York, and William Neuman from Caracas, Venezuela. David M. Herszenhorn and Andrew Roth contributed reporting from Moscow, and Monica Machicao from La Paz, Bolivia.
Correction: July 2, 2013, Tuesday
This article has been revised to reflect the following correction: Because of an editing error, an earlier version of this article omitted the context for a quote by Dmitri S. Peskov, a spokesman for President Vladimir V. Putin of Russia. Mr. Peskov's remark that Edward J. Snowden would face the death penalty in the United States were he extradited and convicted there was a familiar but false jab at that country, not a reference to the precise legalities of the case. The charges Mr. Snowden faces do not carry the death penalty upon conviction.
This article originally appeared in The New York Times.