A businessman with links to Russia's security services has become the latest high-profile figure among the country's elite to die in unexplained circumstances.
Anton Cherepennikov, 40, who was head of the country's largest IT company, ICS Holding, was found dead at his office in Moscow, according to local reports.
The preliminary cause of death was cardiac arrest, according to Russian media outlets.
However, his friend Vasily Polonsky said he did not believe the official reason for his death, independent Russian-language news outlet Baza reported.
"The exact cause of the entrepreneur's death will be determined later," the outlet said.
ICS Holding was used by Russia's Federal Security Service (FSB) for surveillance of citizens' online activities, according to independent Russian newspaper Novaya Gazeta.
The outlet said that the company was the beneficiary of a law, introduced in 2018, that tightened the scrutiny that Russia's security services had over its citizens.
This allowed telecom operators to store audio recordings of all calls and text messages for six months, and internet traffic for a month. ICS Holding faced international sanctions following Russia's invasion of Ukraine.
Cherepennikov was a long-time partner of the oligarch Alisher Usmanov who has faced international sanctions over his links with Russian President Vladimir Putin.
Cherepennikov served on the board of USM as well cellphone operators Megafon and USM Telecom which Usmanov controls, Novaya Gazeta reported.
It means that two figures linked to Putin's regime have died in 48 hours, following the report that billionaire oligarch Igor Kudryakov, a former government official and wealthy businessman, was found dead in his Moscow apartment. According to reports, Kudryakov had been diagnosed with cancer.
"Yet another mysterious death of a top-manager in Russia," tweeted Ukrainian internal affairs adviser Anton Gerashchenko.
There have several recent unexplained deaths of officials and businessmen in Russia.
In June, the body of Artem Bartenev, 42, who served in the Kirovsky District Court in the city of Kazan, was found. He had fallen 12 stories from his apartment window, according to local reports.
Also in June, Yuri Demin, 62, the former head of the State Inspectorate for Road Safety for the Sverdlovsk region, died after falling from the second floor of his summer home.
Pavel Antov, 65, a Russian politician who criticized Putin's invasion of Ukraine, was found dead after a fall from a window in India in December 2022. His death came two days after his friend, Vladimir Bidenov, was found dead in a room at the same hotel.
And Ravil Maganov, 67, the chairman of Russian oil giant Lukoil, was found dead in September 2022. He had fallen from a hospital window in Moscow.
Update 07/22/23, 10:30 a.m. ET: This article has been updated with further information.
