On Monday, a massive database totaling 170 gigabytes of confidential data relating to prominent Russian political figures, business leaders, religious leaders and the Russian military, was published online by hackers belonging to Distributed Denial of Secrets (DDoS). DDoS describes itself as a “transparency collective” made up of mostly Ukrainian and Russian “hacktivists”.

The massive data leak, dubbed “The Dark Side of the Kremlin,” includes tens of thousands of sensitive documents and emails, including personal documents of people in Putin’s inner circle. Some of the documents seem to provide insights into Russia’s activities in Ukraine in the context of its military intervention in the country.

Read more: The Dark Side of the Kremlin: Hacked Russian documents explained