Dmitry Gayev, head of the Moscow subway system from 1995 until last year, died at the age of 61 after suffering a long-term severe illness, his lawyer Alexander Asnis told The Moscow Times, without elaborating.
Interfax reported, citing undisclosed sources in Gayev's inner circle, that he had died Saturday at a Swiss clinic. Life News said he had been suffering from cancer. Asnis declined to comment on that information.
Gayev resigned as metro chief in February 2011, a few days after an Audit Chamber report revealed that the metro had misspent 3.3 billion rubles ($100 million) between 2008 and 2010.
Having been appointed by former Mayor Yury Luzhkov, Gayev's resignation was seen at the time as part of a cadre reshuffle by the newly appointed mayor, Sergei Sobyanin.
Last October, while being investigated for fraud over the allegedly misspent funds, Gayev got permission to go abroad for treatment, his lawyer told Life News.
In April, the Prosecutor General's Office reopened an abuse-of-office case against Gayev on suspicion that he unlawfully received 112 million rubles in royalties after patenting an automated ticket payment system in his name.
The system, which uses magnetic-strip-containing tickets, was introduced in 1997 and is still used today. Gayev registered the patent in 1998 and received royalties between 1999 and 2010.