MOSCOW (AP) — Russian authorities on Monday added popular detective novelist and dissident Grigory Chkhartishvili – known under the pen name Boris Akunin – to its register of “extremists and terrorists.”

On the same day that Russia’s financial watchdog, Rosfinmonitoring, added the Russian-Georgian writer to the register, state media reported that a criminal case had been opened last week against Akunin for “discrediting the army.”

Discrediting the Russian military is a criminal offense under a law adopted after Russia sent troops into Ukraine in February 2022. The law is regularly used against Kremlin critics.

Akunin’s placement on the register comes after one of Russia’s leading book publishers, AST, last week announced that it was suspending the printing and sale of books by Akunin and another popular author, Dmitry Bykov, following their criticism of Russia’s military action in Ukraine.

The decision by AST followed the release of a prank call earlier in December in which the writers expressed support for Ukraine when speaking to pro-Kremlin pranksters known as Vovan and Lexus, who posed as Ukrainian officials.

Akunin, 67, lives in London.