Police swooped on Ablyazov’s house in Mouans-Sartoux, near Cannes, on Wednesday after overlying the property in a plane, according to French magistrate Solange Legras.
“It went off without violence, although there was a certain risk in that he was protected by a sort of private militia,” she told the AFP news agency.
Kazakhstan, Russia and Ukraine have all asked for Ablyazov’s extradition in connection to accusations of fraud involving billions of euros.
France has no extradition treaty with Kazakhstan and officials judged that the agreement with Russia could be annulled, so they are acting on Ukraine’s request.
Kiev has 40 days to address a demand to France.
Ablyazov is accused of granting illegal loans of four billion euros to offshore companies that he allegedly owned when he was head of Kazakhstan’s BTA bank, which was privatised in 1998.
Appointed energy, industry and trade minister by Nazarabayev in 1998, he cofounded the Democratic Choice of Kazakhstan party, a move that angered the president, in 2002.
He was charged with abuse of power and jailed for three years before being pardoned after serving 10 months in jail, then moving to Moscow in 2003 and the UK in 2009.
In an appeal published in the Italian daily La Stampa, two of his children, Madina and Madiyar, appeal to France not to extradite him to Ukraine, accusing Kiev of acting “on behalf of Kazakhstan because our father is the principal political opponent of the dictator Nazarabayev”.
In May Italian police raided the home of Ablyazov’s wife, Alma Shalabaeva, looking for him.
Having failed to find him, they accused Shalabaeva of holding a false passport and deported her and her six-year-old daughter without allowing the right of appeal, a breach of procedure that led to the resignation of a top official in the interior ministry.