Renowned Russian scientist Alexander Kuranov received a seven-year sentence in a high-security prison on Thursday for state treason, according to the Head of the United Press Service of the Courts of St. Petersburg.

Kuranov, who formerly headed a state research institute in St. Petersburg overseeing the Ayaks hypersonic aircraft program, faced arrest in 2021 at the age of 73. The charges against him alleged collaboration with and divulgence of scientific advancements to foreign entities.

Following two closed-door trials due to the case’s classified nature, St. Petersburg’s City Court found Kuranov guilty of state treason. Despite the potential 12-year penalty under Russian law, Kuranov was sentenced to seven years and fined 100,000 rubles ($1,000), with undisclosed mitigating circumstances.

This conviction reflects a broader trend of heightened treason convictions in Russia, notably since tensions have escalated between Russia and the West after the annexation of Crimea in 2014 and the full-scale invasion of Ukraine in 2022. The past year witnessed a surge in convictions for state treason, espionage and disclosure of state secrets, according to data from the Russian Supreme Court.

Kuranov’s case highlights the Kremlin’s crackdown on individuals suspected of sharing sensitive information with foreigners, criticized by many as indicative of state paranoia. Similar incidents involving scientists, journalists and civilians have drawn scrutiny domestically and internationally. Despite this, President Vladimir Putin has consistently emphasized Russia’s hypersonic missile technology prowess, an area where Kuranov had significant expertise.

This latest conviction is the latest in a series of cases involving scientists charged with treason. Kuranov’s sentencing aligns with the broader pattern of legal actions against individuals involved in hypersonic research, reflecting the Kremlin’s strict approach to safeguarding national security interests.