Three patients died in a fire that broke out overnight at a hospital in a town just outside Vienna, Austrian authorities said Tuesday.

The blaze started in a fourth-floor room at the hospital in Moedling, and rescuers were unable to save three men who were in that room, Matthias Hofer, a spokesman for Lower Austria province's health agency, told the Austria Press Agency.

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Destroyed windows are seen on a building of the State Cinic in Moedling, near Vienna, Austria, on May 30, 2023, after a fire broke out in the hospital that led to the loss of three lives. 

Destroyed windows are seen on a building of the State Cinic in Moedling, near Vienna, Austria, on May 30, 2023, after a fire broke out in the hospital that led to the loss of three lives.  (ALEX HALADA/AFP via Getty Images)

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It wasn't immediately clear what caused the fire, which authorities were alerted to shortly before 1 a.m. and that filled the internal medicine ward with smoke. Around 90 patients were evacuated, with some being moved to other parts of the hospital and others transferred to a clinic in nearby Baden.

The fire was extinguished by 3 a.m.