Aluminium producer Norsk Hydro, which is also one of the largest hydropower producers in Norway, has been subject to an extensive cyber-attack, impacting operations in several of the company's business areas.

Details of the attack were announced yesterday, with the company stating that it had isolated all plants and operations and was switching to manual operations and procedures as far as possible.

Norsk Hydro's main priority was to continue to ensure safe operations and limit operational and financial impact, it said in a statement. The problem has not led to any safety-related incidents.

In an update today, the company said it has made progress in securing safe and stable operations. It’s technical team, with external support, has succeeded in detecting the root cause of the problems and is currently working to validate the plan and process to restart the company's IT systems in a safe and sound manner. However, it is still not clear how long it might take restore stable IT operations.

"I'm pleased to see that we are making progress, and I'm impressed to see how colleagues worldwide are working around the clock with dedication to resolve this demanding situation and ensure safe and sound operations," said Hydro's CFO Eivind Kallevik. "I would also like to complement our external technical partners who have done an important job in supporting our efforts, and also relevant authorities, who handle the issue with the diligence it deserves.".

Norsk Hydro still does not have the full overview of the timeline towards normal operations, and it is still to early to estimate the exact operational and financial impact.