Interpol issued a search notice on Sunday for a missing three-year-old girl snatched from France amid a battle for custody between her French father and Russian mother.
France had already alerted police across Europe for signs of the girl and her mother, Irina Belenkaya, and it was at their request that Interpol issued a yellow notice, which is used to help missing persons, often minors.
The Interpol notice, sent out to police forces in its 187 member states, carries a photo of Elise Andre together with a physical description and other identifying details, such as the fact that she speaks French.
Three-year-old Elise was grabbed from her father, Jean-Michel Andre, in the south of France on Friday by two men and a woman. Andre was beaten up during his daughter's abduction.
The move by the international police organisation came as France's embassy in Moscow moved to quash claims that the girl had flown with her mother to Russia.
"The latest information is that they are not on Russian territory," a French diplomat said.
Andre, who appeared on French television covered in bruises and with one eye half-closed, said two unidentified men had beat him up before snatching his daughter as he collected her from school in the southern town of Arles.
Investigators in southern France said they were taking seriously the possibility that the girl's mother had been involved, but for the moment had no hard evidence to prove it.
After a false alert on Saturday that had suggested the girl might be in Russia, they had now turned their attention to Switzerland, local prosecutor Antoine Paganelli told AFP.
"At the present time, the most likely hypothesis comes from the testimony of a Swiss national who says she saw the child accompanied by a woman in a train heading towards Switzerland on Friday," he said.
"The Swiss authorities have been alerted and are taking the necessary steps," he added.
Earlier on Sunday, the Russian authorities said they would inform the French if the girl turned up in Russia.
"But there can't be any talk of detaining the child's mother," said interior ministry spokesman Oleg Yelnikov, Interfax reported.
"A child can't be considered kidnapped if it's by the parent and there's no use of violence or involvement by other persons."
In France, the girl's father told AFP he was certain the third person in the team -- a woman dressed in black and wearing a wig -- had been his estranged wife.
In 2008, Andre himself snatched the girl from a street in Moscow after the mother took the daughter to Russia from him against his will and in defiance of a French court ruling.
Since then, he said, he had been afraid that the girl's mother might try to snatch her back, and had changed home in France several times.
But he told AFP he was ready to go to Russia to get his daughter back, even though he is subject to a Russian arrest warrant.
"I will go to Moscow. I will bring her back... She is my daughter," said Andre.
"If I enter Russia now it would be suicide. You saw what happened to me yesterday," he said. "I have to enter under a false name with a false passport."
While there was no sign of Belenkaya in Moscow, she too has not been shy of putting her side of the story before the public.
In an appearance on a Russian television chat-show after she lost her daughter last year, she said: "Judging from the father's behaviour, it's completely clear that this man has a maniacal attachment to the child that has absolutely nothing to do with a father's love for his child but with other feelings."