Two men have been arrested over an attempted sabotage of several German Navy vessels at Hamburg harbour, German prosecutors and European judicial authorities said on Tuesday.

Investigators said the suspects tampered with warships by disabling electronic safety switches, removing fuel tank caps, puncturing freshwater supply lines and pouring more than 20 kilograms of abrasive material into a ship’s engine.

Authorities said the damage could have caused serious mechanical problems and delayed naval operations if it had not been discovered in time.

The suspects are a 37-year-old Romanian man and a 54-year-old Greek man who were working at the Port of Hamburg.

They were arrested in Hamburg and in a village in Greece during coordinated operations involving German, Greek and Romanian authorities.

Searches were carried out at their homes in Germany, Greece and Romania, where electronic devices and other evidence were seized.

The attempted sabotage was discovered during routine pre-departure checks.

One of the affected vessels was the German Navy corvette Emden, which was preparing for its first voyage to the port of Kiel when the damage was found.

Investigators later identified similar tampering on other corvettes at the Hamburg shipyard.

Authorities said the two men had previously been assigned painting work on the corvette Koeln in June 2025. During that work, they allegedly shut down a control panel, cutting power on the vessel and creating a risk of fire.

Greek police said the 54-year-old suspect was arrested at his home in northern Greece in the early hours of the morning under a European arrest warrant issued by Germany.

Items seized from his residence included several mobile phones, USB drives, a SIM card, a hard drive and documents linked to 19 bank accounts.

Eurojust said the acts could have caused major damage to the ships and delayed their departure, potentially affecting the operations of the German Navy.

Prosecutors said investigations are continuing to establish the full circumstances of the case and to determine whether the suspects were acting on their own or on behalf of others.

German authorities have not confirmed whether the sabotage is linked to any foreign state.

Prosecutors in Hamburg declined to comment on whether Russia is suspected, while Germany’s defence ministry did not immediately respond to requests for comment.

References: Reuters, BBC