NABU conducts searches for the head of the Main Directorate of Internal Security of the SBU Anton Kravchuk, - Ukrainian Pravda Investigative operations are taking place against the background of attempts to conduct searches of the first deputy head of the SBU National State Protection Department Sergey Duka, law enforcement sources told the publication. Earlier, NABU reported that during the investigation, a senior SBU officer threatened with a weapon. According to media reports, we are talking about Duka.