The spill happened overnight nearby a coal-burning power plant, but local environmental officials told AFP that it was unlikely the oil came from the facility. It was still too early however to say what had caused it, they said.

An oil slick-fighting vessel was already at the scene, and a kilometer of oil booms were in the process of being deployed, with the aim of preventing the spill from spreading further.

Inkoo, some 60 kilometers (35 miles) west of Helsinki, is a popular weekend and holiday destination for people living in the Finnish capital.

TERRA.WIRE