Kucinskas is under investigation in Lithuania as well

Vidmantas Kucinskas, the founder of the Arvi business group who has been recently detained in Slovenia in response to Russia's request, is also under investigation by Kaunas Regional Prosecutor's Office, Elena Martinoniene, spokeswoman for Lithuania's Prosecutor General's Office told BNS.

"I can confirm that the Lithuanian prosecution service is carrying out a pre-trial investigation against the person in question and he is named a suspect in this pre-trial investigation," she said.

"Since we are speaking about private persons and a pre-trial investigation, which is now ongoing, the prosecution service cannot provide more information at this moment," Martinoniene said.

She also did not say whether a request would be sent to have Kucinskas extradited to Lithuania.

Russia's Alfa Banks is Kucinskas' biggest creditor.

Kucinskas was detained on July 15 as he was crossing the Slovenian-Croatian border.