WATCH: White House condemns Russia’s reported hostage-taking at closed Chernobyl nuclear plant

WASHINGTON — The White House is expressing outrage at “credible reports” from Ukrainian officials that the staff at the shuttered Chernobyl nuclear plant have been taken hostage by Russian troops.

Watch the briefing in the player above.

Press secretary Jen Psaki said Thursday that “we condemn it and we request their release.”

Psaki says the U.S. has no assessment on the state of the plant where radioactivity is still leaking decades after the worst nuclear disaster in history. But she says hostage taking could hamper efforts to maintain the nuclear facility and is “incredibly alarming and greatly concerning.”

Psaki spoke after Alyona Shevtsova, an adviser to the commander of Ukraine’s Ground Forces, wrote on Facebook that the staff at the Chernobyl plant had been “taken hostage” when Russian troops seized the facility.