ESBU takes interest in "witch" Tykha after MP Zhelezniak’s fraud and income concealment claim. DOCUMENT The Economic Security Bureau of Ukraine (ESBU) has launched an analytical review into possible unlawful actions by Mariia Arefieva, known as "Mariia Tykha." 3 510 16 Previously in trend: Fraudulent schemes Suspicion notice against Mariia Tykha in fraud case