In Finland, as in many countries, investigations of financial crimes tend to be heavy on forensic accounting, bookkeeping evidence, and paper trails, and light on heavy paramilitary weaponry.

So when Finnish authorities over the weekend declared a no-fly zone over an archipelago of islands in the country's southwest, and sent in hundreds of law enforcement agents, including heavily armed officers via amphibious landing craft, it didn't go unnoticed.

The September 22 raids on sites on the Finnish mainland and on islands near the crucial port city of Turku surprised many Finns, who struggled to recall something like this ever happening in peacetime.

It also turned the spotlight on foreigners owning land in Finland -- Russians, broadly, but in this case, a company with Russian ties that has attracted attention for buying up decommissioned Finnish naval vessels at auction, and for spending millions on properties along key shipping routes in the Turku archipelago.

The country's main investigative agency, the National Bureau of Investigations (KRP), said in a September 24 press release that seven people had been questioned, and that three had been detained in the operation. Of the three detained, one was released and arrest warrants had been issued for the remaining two, both of whom were employees of the company under investigation of money laundering and tax evasion.

One of those facing charges was described as an Estonian, and the other a Russian. News reports said a Finnish court on September 25 ordered both held in police custody, pending further investigation.

It will take months to examine the wealth of documents seized in the raids on 17 separate properties, according to the KRP. "Probably at least until the end of next spring," lead investigator Tomi Taskili was quoted as saying.

The reports of shadowy foreign ownership prompted outcry, including questions of possible breaches of national security. In turn, a number of Finnish lawmakers called for backing new legislation, to be voted on this fall, that would put restrictions on foreigners owning Finnish land and property. According to data compiled by Finnish academics, Russians are the largest single group of foreign property holders in Finland.

"This is an important piece of legislation," Tom Packalen, a lawmaker in the Finnish parliament and former police officer in Helsinki, wrote in a blog post.

"The next war, if that ever comes, will not cross the border but [target] strategically important sites in the interior. The war will be started by small groups of people already smuggled in. That is why we have to take care of the law as well as…national defense," he wrote.

Massive Operation

The raid began on September 22 with the announcement of the no-fly zone by the national police agency. The KRP said that 100 of its personnel, as well as 300 from other government organizations -- reportedly including the tax police, border guards, and national defense units -- participated in the operation.

It caught at least one local man, on the island of Sakkiluoto, off-guard.

"My morning wakeup was interesting. I looked down at the shore to see how my boat had survived the storm overnight when I saw two big [inflatable] rubber boats on the beach, each with 20 men in camouflage, holding guns," Leo Gastgivar, who owns a vacation home on the island, was quoted by Finnish public broadcaster YLE as saying.

Finnish media said that the raid, which involved boats, aircraft, and other vehicles, targeted a Finnish-registered company called Airiston Helmi that has ties to Russia. The company, which describes itself as a tourism and accommodation company, had reportedly acquired a number of plots of land located on islands along important shipping lanes that lead into the port of Turku, Finland's sixth-largest city, located about 180 kilometers west of Helsinki.

It also attracted scrutiny for its purchase of decommissioned Finnish naval ships, which reportedly were not repainted, fueling speculation that they might have been intentionally left to resemble Finnish military vessels.

'Bad Business Or Money Laundering'

The KRP did not name the company that was targeted. A police investigator, Markku Ranta Aho, said in a statement only that "the shareholder's owners come from another EU country."

The newspaper Helsingin Sanomat said Airiston Helmi was established in Finland in 2007. The paper said public records showed the company was small, and carried heavy amounts of debt, but had still been able to regularly buy and sell properties in southwestern Finland for millions of euros.

The paper said a national land database showed the company owned several islands and lots along main shipping route leading to Turku.

"There are no commercial grounds for acquiring land, but the roads are strategically important and their military significance is considerable," Packalen wrote in his blog post, published on September 24. "If Airiston Helmi is a truly commercial company, it's run by really bad business people or it's money laundering, which led police to lead a massive operation on the site."

Meanwhile, another newspaper, Ilta Sanomat, reported that Airiston's board was made up entirely of Russian citizens as of 2014. Two years later, an Italian and a Finnish citizen had joined the board, the paper reported.

"I suppose they could observe and evaluate the area traffic, but Finland has so little naval equipment that tracking it would be trivial," Arto Pulkki, a Finnish military expert, told the newspaper.

"They could just as easily do that from the deck of a yacht, without any spy equipment. Maritime intelligence would be useful preceding a military crisis, but once again, it would be more useful for them to have intelligence on islands that are not registered under a Russian name," he was quoted as saying.

Russian Angle

Russian media reported little about the raids. The state-controlled news agency RIA Novosti, citing the Russian Embassy in Helsinki, reported on September 24 that a Russian citizen had been detained as part of a money-laundering investigation, but gave no further details.

Robin Haggblom, a Finnish military observer who publishes a blog under the title Corporal Frisk, pointed out that Airiston Helmi had purchased two surplus Finnish naval vessels in 2010, though there was no indication the purchase was illegal.

In an e-mail to RFE/RL, Haggblom downplayed theories suggesting the Russia-linked company had been buying up real estate as part of a secret infiltration by the Russian military intelligence agency known as the GRU.

"Happy enthusiasts have already decided that Airiston Helmi is a GRU-run operation, complete with vessels for false-flag operations and barracks for spetsnaz units to stay in after infiltrating the country prior to war. It is a possibility, but I am unconvinced," he wrote.

However, he pointed to growing evidence from many experts that have documented Russian intelligence agencies working with shadowy private companies, and even criminal entities, to do operations outside of Russia.

The outcry over the raid was enough to prompt Finnish President Sauli Niinisto, in New York attending the United Nations General Assembly, to weigh in, telling Finnish reporters that there had been concerns about the company in question for some time.

Another Finnish newspaper, Iltalehti, quoted two unnamed generals from the Finnish armed forces as saying it was no run-of-the-mill criminal investigation, that Finnish authorities were hiding the true motivation behind the raids, mainly in order to not provoke the Russians.

"A criminal investigation is less of a provocation than a military operation," one of the officers was quoted as saying. "I believe this is clear to everyone."