A cargo ship caught fire and sank in the Black Sea after being hit around 32 kilometres from the village of Sfantu Gheorghe in the Danube delta - inside Romania's exclusive economic zone. That means in the waters of a country that is a member of both NATO and the European Union, not in the Ukrainian waters where strikes like this have become routine.

After the impact a fire broke out on board, after which the vessel sank. All 12 crew members were rescued; one sailor was injured, the rest were evacuated once the ship's condition became critical.

Nobody is saying who fired

And that is where the story stops. The Romanian authorities have yet to establish what exactly hit the ship, where the strike came from, and whether the vessel was a deliberate target. So far there is no answer to any of those three questions.

Nor is it the first incident in that belt. The same area has already seen several security events linked to shipping, to drones and to the war in Ukraine - which makes establishing responsibility for individual cases harder still. When incidents line up one after another, each new one slides more easily onto the pile marked "unresolved".

That is exactly what is worth noting. A ship hit in the economic zone of a NATO member, twelve people rescued, a vessel on the seabed - and not one name. A war officially fought in one place lost the tidy borders it had at the start a long time ago.

Wheat, fertiliser and oil travel across the Black Sea - it is one of the main export corridors for grain from this part of the world. Every ship hit in it pushes insurance premiums up and reroutes traffic, and insurers do not wait for an investigation before recalculating the risk zone.

The situation is being monitored, and further information is expected from the Romanian maritime and security services. Experience with cases like this says the answer, if it comes at all, will arrive long after the attention has moved on.