Inspectors will check an underwater pipeline for pollution after it caught fire on a frozen river in Russia's Siberia, federal monitoring service Rostekhnadzor said Sunday.
First reports suggest around 700 tons of liquefied petroleum gas (a mixture of propane and butane) could be on site, Rostekhnadzor spokesperson Andrei Vil said on his Telegram account.
The pipeline's owner Russian petrochemicals giant Sibur said the gas leak happened Saturday, causing a short fire on the frozen River Ob in the oil-rich Khanty-Mansiysk region in Western Siberia.
It happened 44 kilometers (27 miles) from the nearest residential area and there were no "risks for the population and the environment", the company added.
But Vil said on Telegram that "statements indicating the absence of risk for the environment raise serious doubts" because of the amounts of liquefied petroleum gas on site.
The cause of the leak is still being established, said Sibur.
A Sibur regional official Alexander Teplyakov said Sunday the incident was under control but that the company would pay for any damage caused by the incident.
Teplyakov, quoted in a statement from the local authorities, said 27 people and 12 units of machinery were currently on site.
Samples would be taken from the surface of the water to determine any damage to the environment, he added.
Russia frequently suffers environmental disasters, often due to the country's ageing infrastructure or to negligence.
Last month, mining giant Norilsk Nickel was fined close to $2 billion for a fuel spill that leaked tons of diesel into rivers in the Russian Arctic.