An influx of jellyfish has forced the shutdown of two reactors at the Torness nuclear power station in East Lothian.
Seawater is taken into the plant and filtered before it is used to cool the reactors, but the number of jellyfish coming through the system resulted in the filter systen becoming clogged.
Jellyfish, seaweed or other debris causing the flow of cooling water to be reduced is not an unusual situation.
The shutdown, which took place on June 28, was done as a precaution and the cooling sytstems performed properly during the procedure and both reactors are now safely shut down.
A spokesperson for EDF Energy, the company that runs the power station, said: "This was a precautionary action and the shutdown cooling systems performed in a satisfactory manner and both reactors were safely shut down.
"At no time was there any danger to the public. There are no radiological aspects associated with this event and there has been no impact to the environment."
The Office of Nuclear Regulation (ONR) has been fully informed about the situation.
A spokesman for the Office for Nuclear Regulation said: "ONR is aware of the situation at Torness and is being kept informed of developments. The licensee reported to ONR that it shutdown both reactors in order to maintain the plant within permitted temperature/safety limits.
"ONR's site inspector will follow up on the event with the licensee at the next available opportunity. These situations are not uncommon and are also sometimes caused by fish or seaweed. Power stations have a pre-planned course of action which they adopt if such circumstances arise."
The operator says that the reactors will be restarted once the jellyfish situation subsides.
Work to clear the jellyfish from the water near the power station and monitoring the area for more of the creatures is now under way.news.stv.tv/scotland