A cyber attack on a Norwegian shipping services firm ensnared about 70 companies and 1,000 ships.

Oslo-based DNV, one of the world’s top ship-classification firms, suffered a ransomware cyberattack on January 7, it said in a statement on its website. The attack didn’t affect the ships’ ability to operate, but DNV didn’t spell out what was disrupted.

DNV, which also provides fleet-management software, is working to restore the functionalities of its ShipManager servers. There are no indications that any other DNV data or servers are affected, and the attack has been reported to the Norwegian police, it said.

Cyber threats are not new to the wider maritime shipping and logistics industries, but the incident comes at a time when supply lines are stretched and Russia’s invasion of Ukraine brought greater scrutiny of such risks.