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By Steve Scherer
ROME, Sept 25 (Reuters) - The family of a Kazakh oligarch accused of embezzling billions of dollars from his former bank filed a criminal complaint on Wednesday against unnamed Italian government officials accusing them of helping Kazakh diplomats kidnap his wife and six-year-old daughter.
Mukhtar Ablyazov's 25-year-old daughter Madina formally accused Interior Ministry officials, who the court must identify through an investigation, of taking her family members into custody and putting them on a plane to Kazakhstan in May.
His wife Alma Shalabayeva and his young daughter were seized in a police raid on the villa where they had been living outside Rome and were flown to Kazakhstan less than three days later on a private plane.
Ablyazov, 50, is at the centre of a long and tortuous legal battle with BTA, the Kazakh bank he once controlled and which is now majority owned by the state of Kazakhstan.
Earlier this year, a British judge said Ablyazov instigated a massive fraud against the bank, which has so far won court approval to seize around $3.7 billion of his assets.
Ablyazov was arrested in France in July after 18 months as a fugitive and remains in custody facing possible extradition. Russia, Ukraine and Kazakhstan have laid charges against him.
He denies the charges, which he says are aimed at silencing him as a political opponent of Kazakh President Nursultan Nazarbayev.
Madina's lawyer Astolfo Di Amato told reporters in Rome the speed with which Ablyazov's wife and daughter were transferred to Kazakhstan was "exceptional".
On arrival, Shalabayeva was placed under criminal investigation, accused of paying bribes to immigration officials to obtain false passports. She is now living with her parents in Almaty, but is not allowed to leave the city.
"We are convinced that there were abuses, that there were grave failures, and that the prosecutor's office can shed light on what happened," Di Amato said.
Madina, who lives in Switzerland, also accused three Kazakh diplomats, including the ambassador to Italy, of kidnap. The maximum sentence for the crime is 15 years in prison.
An Interior Ministry spokesman had no immediate comment. The Kazakh embassy in Rome did not respond to requests for comment.
Italy has admitted that there were irregularities in the case and Prime Minister Enrico Letta announced the revocation of Shalabayeva's expulsion order in July. She has since asked to be allowed to return to Italy with her daughter, but Kazakh authorities have rejected her request, Di Amato said.
Amnesty International, Human Rights Watch and other groups have appealed for authorities to allow Shalabayeva to return to Italy. They say Ablayzov should not be extradited because he would likely face political persecution at home. (Reporting by Steve Scherer; Editing by Angus MacSwan)