Matvey was arrested in September 2021 in connection with a criminal case opened for online comments following the deaths of KGB officer Dmitry Fedosyuk and IT specialist Andrei Zeltser in Minsk.
In October 2022, he was found guilty of "inciting hatred or discord" and "insulting a government official," and sentenced to imprisonment and a large fine.
According to human rights activists, he was released in the summer of 2024, having fully served his sentence.
