Ukraine's Interior Minister Arsen Avakov has said that the participants in the illegal breakthrough of the Polish-Ukrainian border at the Shehyni checkpoint are obliged to "immediately" pass the legal procedure for registering their crossing at the border, as well as giving testimony at the police station for giving testimony.

He said on his Facebook page on Monday morning that the National Police have opened a criminal case pursuant to Article 332 "Illegal transfer of persons through the state border of Ukraine." A formal investigation of the incident has begun.

"It's a 'heavy' article. I'm sure the prosecutor's office will support us, just like the courts. Every person who illegally crossed the border and attacked border guards and policemen will be punished by the law," the minister said.

"Saakashvili and all those illegally crossing the border should immediately choose from two options: to arrive at the checkpoint Shehyni and undergo the registration procedure and/or to arrive at the branch of the Migration Service. All participants in the 'breakthrough,' including people's deputies should come to the police for testimony," Avakov said.