Russia on Thursday launched a probe into the Financial Times and the New York Times after the newspapers said local authorities could be vastly under-reporting deaths from the coronavirus in the country.
State communications watchdog Roskomnadzor said it was studying the reports to establish whether they violated the country's law against disinformation.
Contacted by AFP, the watchdog did not say whether it planned to punish the media outlets.
Foreign ministry spokeswoman Maria Zakharova demanded that the FT and the NYT retract the "disinformation", adding that formal letters had been sent to the newspapers' editors-in-chief.
"We see -- and there is more and more evidence -- that unfortunately certain forces in the West are seeking to use the current crisis in the world to discredit government efforts in a number of states, to destabilize the situation," Zakharova told reporters.
She said the FT and NYT stories were suspiciously similar and published the same day.
Formal complaints will be also sent to the OSCE Representative on Freedom of the Media; Audrey Azoulay, UNESCO Director-General and the UN secretariat, Zakharova said.
There was no immediate comment from the FT, while the NYT said it stood by its report.
"We're confident in the accuracy of our story, which is based on publicly available government records and interviews with experts from government-run institutions. No facts in our story are in dispute," The New York Times Vice President for Communications Danielle Rhoades Ha said in a statement.
Russia has the world's second-highest number of coronavirus cases but has registered 10 times fewer deaths than Britain, France, Italy and Spain.
As of Thursday the country had 252,245 confirmed coronavirus infections and 2,305 deaths.
Critics accuse Russia of under-counting the number of deaths to downplay the scale of the crisis. They say it is hard to believe that the country's under-funded healthcare system is managing better than those in the United States and western Europe.
Authorities have denied falsifying the numbers, saying they are only counting deaths caused directly by the coronavirus and that since the pandemic came later to Russia, it was able to learn lessons from the experiences of western Europe.