The Russian human rights group Memorial is calling for the release of a 77-year-old former space researcher who was sentenced to prison on a treason conviction in 2016.
In an August 28 statement, Memorial said that Vladimir Lapygin is a political prisoner and called for his immediate release.
Lapygin was sentenced to seven years in prison in September 2016 after a Moscow court found him guilty of handing secret information to foreigners.
Memorial said that the information at issue cannot be considered as secret as many scientists in Russia have said that it is freely accessible from different open sources.
Lapygin denies any wrongdoing, saying he never had any access to classified information.
Before his arrest in May 2015, Lapygin worked for a research branch of the Russian space agency Roskosmos.
His case is one of several in recent years in which scientists and scholars have been accused of selling secrets.
Government critics say that they are frequently prosecuted for disseminating open-source information and that such cases cast a chill over research, science, and the academic community in Russia.
