Head of the Security Service of Ukraine (SBU) Vasyl Hrytsak has said that he does not rule out the 'Russian trace' in setting on fire the office of judge Mykola Didyk, who presides in the trial against Russian servicemen Yevgeny Yerofeyev and Alexander Alexandrov.

"It is a very convenient cover up - to burn the office and to say that the materials of these criminal proceedings were in that office... I do not rule out...'a Russian trace' because we are analyzing everything that we have received from public and private sources, and see that someone wants to do everything possible to delay the consideration of a the case against the Russian intelligence officers," the SBU chief said at a briefing in Kyiv on Friday.

As reported, unknown persons threw bottles filled with a flammable liquid into the premises of Kyiv's Holosiyivsky District Court last night, causing a fire at the office of the judge who is presiding over the trial of Russian intelligence officers Yevgeny Yerofeyev and Alexander Alexandrov.

The office of the judge presiding over the Russian citizens' trial was partially damaged in the fire.

"According to the judge, the documents as part of these criminal cases were not damaged. Law enforcement agencies are considering several theories behind the offense. The main one of them is the judge's professional activities," the deputy chief of the National Police department in Kyiv, Oleksandr Pyvovar, said.