US issues formal complaint to Russia over response to suspected death related to plague lab

ABC News has learned that the U.S. issued a formal diplomatic complaint known as a démarche over the Russian government's response to the reported death of a lab worker from an anti-plague institute in Siberia, urging the country to increase transparency surrounding the incident.

"We have officially requested additional information from the Russian government. We are also in official communication with other countries around the world to share information," a State Department spokesperson said.

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