Hacking collective Anonymous claims to have broken into the Central bank of Russia.
News of Anonymous's hack was shared on Twitter by one of the group's accounts, @YourAnonTV.
The exact nature of the files threatened for release has not been revealed, but Anonymous claims they include 'secret agreements'.
The Central Bank of Russia has been fighting a rearguard action to protect the Russian economy amid a deluge of sanctions by Western powers following the invasion of Ukraine.
Anonymous, which has declared 'cyber war' against Russia, also claims to have remotely accessed unsecured printers across the country to print out 'anti-propaganda' messages about the war across the border.