Finland's foreign affairs ministry said on Friday it had summoned Russia's ambassador and requested an explanation after a Russian IL-20 reconnaissance plane was suspected of having violated Finnish airspace on Thursday.
Finland's border guard said on Friday that the duration of the suspected violation in the Western Gulf of Finland was around 3 minutes, and the aircraft was at its deepest around 4.7 nautical miles (8.7 km) inside Finnish territory.
Russia's embassy to Finland did not immediately respond to a request for comment when contacted by Reuters via phone and email.
Finland's border guard has launched a preliminary investigation into the suspected violation.
