Because of his works written in Bulgarian, Markovski was declared a traitor of the Macedonian nation and in 1975 was under the protection of the Bulgarian secret service as it was believed an assassination was being planned by the Yugoslav secret police, the UDBA. Only seven days prior to his death, Markovski stated in an interview for Bulgarian National Television that the ethnic Macedonians and the Macedonian language are a result of a Comintern conspiracy.
Markovski was accused of treason for his writings in Bulgarian, which were seen as promoting the idea that ethnic Macedonians and the Macedonian language are a product of a Communist conspiracy. This accusation led to him being placed under protection by the Bulgarian secret service due to fears of an assassination plot orchestrated by the Yugoslav secret police.