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"This theory has several 'subtheories.' In particular, Sheremet wrote a book with (Boris) Nemtsov, published materials exposing the current regime in the neighboring state, so this is also a theory, and this is also being considered," he said at a briefing in Kyiv on December 12.

Read alsoPolice detain suspects in Sheremet murder case – interior minister

First Deputy Chief of the National Police Yevhen Koval, in turn added, that the destabilization of the situation in Ukraine through the assassination of a well known person is the investigators' major theory, however, other theories are also under consideration.

On December 12, the National Police revealed the identities of five suspects in Sheremet's murder: former Donbas war volunteer and member of the Riffmaster band Andrii Antonenko, civil volunteer and doctor Yulia Kuzmenko (nom de guerre "Lysa," or "Fox"), Yana Duhar, Inna Hryshchenko ("Puma") and her husband Vladyslav Hryshchenko ("Bucha").

UNIAN memo. Pavel Sheremet, a journalist from Belarus who was residing in Kyiv, was blown up in a car on the morning of July 20, 2016. Police opened a criminal case under Clause 5 of Part 2 of Article 115 of the Criminal Code of Ukraine (felonious homicide committed in a way dangerous for many people's life).