In keeping with Ukraine's Criminal Code, high treason is punishable by imprisonment for a term of 12 to 15 years.

The prosecutor's office in Ukraine's Zakarpattia region jointly with the SBU Security Service of Ukraine is investigating the issue of Hungarian passports to Ukrainian citizens in the town of Berehove as high treason.

"This information was included in the register of pretrial investigations and criminal proceedings were launched on deliberately committed actions by citizens of Ukraine to the detriment of the sovereignty, state and information security of the country, which has signs of a criminal offense stipulated in Part 1 of Article 111 of the Criminal Code of Ukraine, i.e. high treason," the press service of the regional prosecutor's office told UNIAN.

Read alsoHungary's consulate reportedly issues Hungarian passports to Ukrainians (Video)

The case concerns a video posted by one of the central media outlets that shows citizens of Ukraine, swearing an oath of allegiance to another state, receiving passports of Hungarian citizens, it said.

Officials of the institution where the events was taking place recommended that the newly converted citizens should conceal their foreign citizenship from the government of Ukraine.

The pretrial investigation is conducted by the investigation department of the Office of the SBU Security Service of Ukraine in Zakarpattia region. The investigation is being supervised by the prosecutor's office in Zakarpattia region

Part 1 of Article 111 of the Criminal Code of Ukraine covers high treason, that is an act willfully committed by a citizen of Ukraine in the detriment of sovereignty, territorial integrity and inviolability, defense capability, and state, economic or information security of Ukraine: joining the enemy at the time of martial law or armed conflict, espionage, assistance in subversive activities against Ukraine provided to a foreign state, a foreign organization or their representatives, which is punishable by imprisonment for a term of 12 to 15 years.

Part 2 of Article 111 says that a citizen of Ukraine shall be discharged from criminal liability where, he or she has not committed any acts requested by a foreign state, a foreign organization or their representatives and voluntarily reported his or her ties with them and the task given to government authorities.