Russia declared the umbrella organization Memorial International a “foreign agent” in the fall of 2016. The organization is comprised of a patchwork of smaller groups that work in the fields of philanthropy, human rights advocacy and historical research.

Russia’s Justice Ministry is inspecting a renowned human rights group based on allegations that it illegally acted as a “foreign agent.”

The Justice Ministry on Monday began an inspection into Memorial’s Research and Information Center for undeclared “foreign agent” activity, Memorial said in a statement on its website Monday.

The ministry’s inspection is based on “information received from a government agency,” Memorial said, citing a letter it had received in December from the authorities. The notification, received Dec. 19, did not identify the government agency in question.

Memorial was co-founded 30 years ago by prominent activist Lev Ponomaryov, who was detained for 16 days last month for allegedly organizing protests in support of a group of teenagers accused of extremism. Two of Memorial regional heads Oyub Titiyev in Chechnya and Yury Dmitriyev are currently under investigation on charges which their supporters say are politically motivated.

Under Russian law, any NGO that takes part in “political activity” and receives money from abroad must declare itself as a foreign agent.