English-language website Japan Today is reporting that tons of dead sardines have washed up onto the port in Isumi City of Chiba Prefecture in Japan.

The incident begun on June 3, and now the port is covered in dead, rotting fish — Chibanippo reports that a total amount of 200 tons is expected.

The image below has been doing the rounds on twitter shows a carpet of dead sardines:

Reports suggest that the fish died of a lack of oxygen, but what caused that isn't quite clear. Online comments, Japan Today reports, are suggesting the dead fish are an omen, the sign of a coming disaster.