MOSCOW -- Russian scientist Roman Kovalyov, convicted and sentenced to a lengthy prison term in 2020 on a high-treason charge that he and his supporters rejected, has died of cancer.
The Pervy Otdel (First Unit) human rights group said on April 27 that Kovalyov, a former senior official at the Central Research Institute of Machine Building (TsNIIMash), was released from prison two weeks earlier to allow him to die at home.
In June 2020, the Moscow regional court sentenced Kovalyov to seven years in prison after he was convicted of treason.
Details of the case have not been made public as its materials were classified.
Kovalyov was working with Viktor Kudryavtsev, a researcher at TsNIIMash, Russia's leading rocket and spacecraft scientific center, which is located in the city of Korolyov near Moscow.
Kudryavtsev was arrested in July 2018 on suspicion of passing classified data on hypersonic technology to a research group in Belgium.
Kudryavtsev's lawyers said at the time that he had rejected a deal with investigators who wanted him to testify against Kovalyov in exchange for being transferred from pretrial detention to house arrest.
Kudryavtsev suffered a heart attack while in custody. He was released from pretrial detention in late September 2019 and ordered not to leave Moscow while an investigation was conducted.
In April 2021, Kudryavtsev died of lung cancer at the age of 77.
The case against Kovalyov and Kudryavtsev was one of several in recent years in which Russian scholars and scientists have been accused of treason or disseminating classified or sensitive information.