"Experts examined the seat of fire and found no traces of an arson," RIA Novosti's interlocutor said.
According to his data, the prosecutor's office has already initiated criminal proceedings.
"An electrical fault or carelessness with flame are the most probable versions of the fire," he added.
The fire occurred in Moscow Court of Arbitration at 21.00 Moscow time yesterday. It took firemen five hours to extinguish the fire. Nobody suffered in the accident.