Finland’s defence ministry said the incident was “rather brief”.
They said the plane entered Finland’s airspace at roughly 7am yesterday morning.
The plane was identified as a passenger or cargo plane and no a military jet, Finnish state broadcaster Yle said.
They said the Russian Tupolev TU-154 the Gulf of Finland near the city of Porvoo.
The area is close to a route used by Russian aircraft between the cities of St Petersburg and Kaliningrad.
The Finnish borde guard is now carrying out an investigation into the incident.
It came as Finland prepared to celebrate the 100th anniversary of the country’s declaration of independence from Russia.
This is a developing story, more to follow…