Russia warns against spreading 'false information' as reports emerge of second plague case

The Kremlin on Wednesday appeared to reject reports of a second suspected plague case in Siberia, telling reporters when asked about the accounts that most media reporting on the situation was "false".

The United States, the European Union and the World Health Organization have all called on Russia to be transparent over the reported plague death of a laboratory technician at a plague research institute in Siberia's Irkutsk region last week.

WHO chief Tedros Adhanom Ghebreyesus also called Wednesday for Moscow to clarify "media reports of a second employee with pneumonia of undetermined cause".

Read moreRussian lab worker's death sparks plague fears as unverified claims spread online

Asked about the reports, Kremlin spokesman Dmitry Peskov told reporters that "the media reports a great deal".

"And the vast majority of what the media is reporting regarding this situation is false information," he insisted, calling on people to rely solely on official statements from Russia's health watchdog Rospotrebnadzor.

Peskov also said he had "no information" regarding a formal request from Washington for clarifications about the situation.

A source close to the matter had said on Tuesday that the United States had made such a request via a confidential diplomatic communication, known as a demarche.

Russian news outlet People of Baikal reported Friday that the dead woman – named as 28-year-old Darya Shipilova – may have contracted pneumonic plague from a broken test tube.

Other media reported a possible link between her death and a lab accident at the facility.

The People of Baikal outlet also said up to 200 people with whom she may have had contact were under quarantine.

But Russian authorities say the cause of death is not confirmed and Rospotrebnadzor has denied claims circulating in a document online that special measures have been put in place.