A fire at a wooden pallet factory near Moscow was spreading fast, Russian agencies reported late on Tuesday, citing emergency services.
Russia's RIA news agency reported the fire was consuming some 6,000 square metres (64,600 square feet), doubling the area it reported only minutes earlier.
Russia's TASS news agency cited a statement from the Moscow region prosecutor's office as saying that according to preliminary information, an electrical short caused the fire.
There was no immediate information on possible casualties.