Russian authorities have been pressed for an explanation after Olympic torches produced by a missile maker and used in the relay for the Sochi Winter Games went out four times.
The flame was extinguished twice on the first day of the relay and twice yesterday.
A spokesperson for the Siberian torch manufacturers says 16,000 torches were made.
The factory is known as the maker of ballistic missiles for Russian submarines as well as parts for the Proton rocket used in the country's space programme.
There was no tender process for the $10 million torch-making contract and it's unclear why the factory was picked for the job.