Officials at OKG, which runs the Oskarshamn nuclear power plant in southeastern Sweden, say they had to shut down reactor three on Sunday after tons of jellyfish clogged up pipes bringing cooling water to the plant.
OKG spokesman Anders Osterberg said Tuesday that the water was needed to cool the reactor's turbines but there was no risk of an accident.
Osterberg says the plant faced a similar scenario in 2005 when jellyfish clogged the water intake pipe of reactor one.
The Oskarshamn facility has three reactors, with number three being the world's largest boiling water reactor.
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