Kazakh authorities accused former Kazatomprom Mukhtar Dzhakishev of money laundering, amid ongoing investigation into his role in alleged theft and illegal sales of uranium assets to foreign companies.
The Committee for National Security (KNB) reportedly launched a new criminal probe into his affairs, nine months after Dzhakishev's initial arrest.
"It's a new case which has been opened within the framework of an ongoing investigation," said Nurdaulet Suyundikov, a prosecutor general's office spokesman.
In May, Dzhakishev and several other top officials from the national nuclear company Kazatomprom  were arrested and accused of large-scale misappropriation of state funds. The KNB said that a number of uranium deals Dzhakishev closed while at the helm of Kazatomprom were illegal under existing Kazakh law,  causing anxiety among foreign investors in Kazakhstan.
The arrest of Dzhakishev, a well-respected businessman, has drawn attention of local and international business and human rights community while Dzhakishev has denied all accusations.
"It is obvious that I cannot count on justice in my own country and my fate has already been decided," he wrote in a letter published by his lawyers this week. "But I want to tell the people of Kazakhstan that I am innocent."
The case has fuelled speculation of an intensifying power struggle within the political elite and Russian involvement in the affair, alleged in leaked interrogation videos by Dzhakishev himself.