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Here are all the Russian oligarchs who’ve died under strange circumstances this year

April 26, 2022, 11:00 AM UTC

Last week, two more Russian oligarchs were found dead alongside their families within 48 hours of each other in alleged murder-suicides. They’re the latest of a series of high-profile Russians to die in mysterious circumstances in recent months.

It’s not the first time there have been reports about Russian officials dying suspiciously, and Russian President Vladimir Putin has long been known to take extreme measures to silence his opponents. In 2017, USA TODAY published an investigative report detailing at least 38 oligarchs who died or went missing over a three-year span.

In the early months of 2022, at least six prominent members of Russia’s upper class have been found dead under strange conditions. Here’s a list of every Russian oligarch we know about that has died this year:

Vladislav Avayev

On April 18, Vladislav Avayev and his wife and daughter were found dead in their Moscow apartment, according to TASS, a Russian state-controlled news agency. 

Preliminary evidence suggested that the deaths were the result of a murder-suicide, TASS reported. Avayev was found inside his multimillion-dollar Moscow apartment holding a pistol, which was presumably used to kill his wife and 13-year old daughter.

Avayev was the former vice president of Gazprombank, which is Russia’s third largest bank, and services energy giant Gazprom

Sergey Protosenya

Just two days later, another high-profile Russian was found dead in shockingly similar circumstances. 

The body of Sergey Protosenya, a former executive at Novatek—Russia’s largest independent natural gas producer—was found hanged outside the Spanish villa he and his family were renting. His wife and 18-year old daughter were found stabbed to death in their beds, according to Spanish news station Telecinco

Protosenya, 55, accumulated a net worth of more than $433 million, according to Telecinco. 

An initial investigation by local law enforcement initially showed that the family’s deaths had resulted from a murder-suicide, but investigators did not ruling out the possibility that all three had been murdered, according to Spanish news outlet El Punt Avui.

Shortly after their deaths, Novatek, where Protosenya worked from 1997 until 2015, released a statement casting doubt over the theory that he murdered his wife and daughter. 

“[Protosenya] established himself as an outstanding person and a wonderful family man, a strong professional who made a considerable contribution to the formation and development of the Company,” Novatek said in the statement. “Unfortunately, speculations have emerged in the media about this topic, but we are convinced that these speculations bear no relation to reality.”

Vasily Melnikov

Last month, Russian billionaire Vasily Melnikov was also found dead in his multimillion-dollar apartment in the Russian city of Nizhny Novgorod alongside his wife and two sons, according to Russian newspaper Kommersant and reported by Newsweek

All three Melnikovs died from stab wounds. According to Kommersant, police investigations determined that Melnikov killed his wife and sons before committing suicide. 

According to reporting from Newsweek, neighbors and relatives of Melnikov have come out saying they struggle to believe Melnikov is responsible for killing his family. 

Before his death, Melnikov was an executive at the medical firm MedStom. The company has suffered immensely as a result of the economic sanctions placed on Russia in the aftermath of the country’s invasion of Ukraine, according to Ukrainian news outlet Glavred and reported by Newsweek. 

Mikhail Watford

In late February, just days after Russia officially invaded Ukraine, Mikhail Watford was found hanged in the garage of his Surrey, U.K., home. His wife and children were home at the time, although they were unharmed. 

The Ukrainian-born Russian, 66, made his millions as an oil and gas tycoon after the fall of the Soviet Union, according to the BBC.

Born with the last name Tolstosheya, Watford changed his name after moving to the U.K. His death is under investigation by Surrey Police, who told the BBC in early March that “there were not believed to be any suspicious circumstances at the time.” 

Alexander Tyulyakov

On February 25, just three days before Watford’s death, former Gazprom executive Alexander Tyulyakov, 61, was found hanged in the garage of his apartment building near St. Petersburg, according to Russian newspaper Gazeta and reported by Newsweek. 

Police told Gazeta that they found a suicide note next to his body, which led investigators to believe he died by suicide. 

Tyulyakov’s suicide is currently being investigated by Gazprom, whose security units arrived at the scene with police in February, according to Gazeta.  

“In all cases, there are widespread suspicions that the deaths may have been staged as suicides, but who did this and why?” Grzegorz Kuczyński, director of the Warsaw Institute’s Eurasia Program, told Fortune about the recent string of deaths involving oligarchs. 

Leonid Shulman

Like Tyulyakov, Leonid Shulman was a top executive at Gazprom when he was found dead by apparent suicide in January, before Russia had invaded Ukraine.

Shulman, 60, similarly was found next to a note that led police to believe he committed suicide, according to the Gazeta and reported by Newsweek

Shulman’s death came just months after a probe into his alleged fraud at Gazprom was opened, according to Fortune. According to a note from the Warsaw Institute, Gazprom is also currently investigating Shulman’s death.

Gazprom, Novatek, and Medstom did not immediately respond to Fortune’s requests for comment.

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