The change in alert level is based on an “overall impression of the threat situation”, the Energy Agency said in a statement.

Energinet is responsible for the overall operation of Denmark’s electricity and gas supply system.

At the end of September, the Energy Agency requested a higher alert level following explosions at the Nord Stream gas pipelines near Danish island Bornholm in the Baltic Sea.

Orange, the second-highest level, means that companies in the sector are to be alert to security at their facilities.

The higher alert level means that “the physical security of vital buildings and installations is checked,” Danish Energy Agency director Kristoffer Böttzauw told news wire Ritzau last month.

“You make sure that fences are intact, that security cameras are working and that there are regular patrols. And you limit access as much as possible,” he said.

At yellow level, “extraordinary contingencies” are reduced, but alert is still raised meaning increased surveillance is still in place.

The threat level rating by the energy authority is based on a range of parameters including assessments issued by national intelligence agency FE.

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