The Finnish Navy has responded to an increase in the number of reported sightings of submarines in Finnish waters.
The sightings are especially noteworthy because the Finnish fleet does not include any submarines, meaning any such vessel spotted in Finnish waters belongs to another state.
Earlier this week, a member of the public photographed a sub in the Archipelago Sea — leading to some intense online speculation about its possible origin. The Finnish Navy later clarified that the submarine in question is Swedish, and it was participating in the Narrow Waters 25 naval exercise at the time.
According to Annele Apajakari, Chief Public Affairs Officer with the Finnish Navy, it is not unusual to see a submarine in Finnish territorial waters — but information on their numbers and operations is confidential.
The navy further explained that submarines operating in Finnish territorial waters must obtain permission from the Finnish Defence Forces, unless the operation is in accordance with international agreements that are also binding on Finland. This includes transiting through Finnish territorial waters on the way to another destination.
Apajakari noted that Sweden, Germany, Poland and Russia are all known to have submarines active in the Baltic Sea area.
However, she added that an increase in the number of reported sightings does not necessarily mean an increase in submarine activity.
"People are on the move a lot more these days and everyone has a smartphone in their pocket," Apajakari said.
She further noted that many of the reported sightings turn out to be false.
For example, Halliluoto and Lokkiluoto — two small islands located off the coast of Helsinki — are often mistaken for submarines due to the presence of military structures on both.
The official advice to members of the public who spot a submarine in Finnish waters is to treat it as they would any other vessel.
"It follows the same rules of giving way, speed limits and other waterway traffic rules as other vessels," according to Aleksi Uttula of Traficom, the Finnish Transport and Communications Agency.
In addition, a submarine's flag must be visible when it emerges to the surface.
