KIEV (AFP) - Ukraine's interior minister said on Friday that police had detained the head of the Naftogaz state oil and gas company on suspicion of embezzling at least US$4 billion (S$5 billion) during the rule of ousted president Viktor Yanukoych.

Interior Minister Arsen Avakov said in a statement published on his Facebook account that Naftogaz chief Yevgen Bakulin is suspected of heading a "criminal group" whose members include other senior current and former Ukrainian government members.