The Trump administration is closely watching reports of a suspected fatal plague infection in Russia and is urging Moscow to be transparent, officials said Sunday night.

The Moscow Times reported this weekend that health officials in Siberia’s Irkutsk region placed nearly 200 people under medical observation after a laboratory worker died from the plague.

Alexei Tsydenov, head of the neighboring republic of Buryatia, confirmed that a lab worker who broke a test tube of live bacteria had died from an unspecified form of plague, the Times reported.

State Department officials told NewsNation and Fox News that U.S. officials were monitoring the situation and details were still vague. 

 “We are aware of reports of a fatal case of suspected pneumonic plague in Irkutsk Oblast, Russia. We are monitoring the situation closely with the CDC and our other interagency partners,” one official told NewsNation.