A close friend of Finland’s embattled prime minister Sanna Marin may have had his or her phone or social media accounts hacked by Russian intelligence operatives, a leading Finnish cybersecurity expert says.

Speaking to the Finnish newspaper Iltalehti about the uproar over leaked videos showing Ms. Marin dancing and drinking alcohol at a private but roisterous party, Petteri Järvinen said that “It could be that some social media account or phone with the videos has been hacked or broken into by the Russians.”

On Thursday, a video leaked on social media showed the 36-year-old prime minister dancing at a party and lip-syncing a song. Finnish media reports hinted that drugs may have been in use at the party, prompting calls from at least one opposition politician for Ms. Marin to take a drug test.

On Friday Ms. Marin told a news conference, “I have taken a drug test for my own legal protection, the results of which will come in about a week.”

It was not clear which friend or friends of the premier may have had their phones or social media accounts hacked.

Subsequent to the short video being leaked on Thursday, another video surfaced — also on social media — in which Ms. Marin, who is married with one daughter, showing the premier dancing hip-to-hip with Olavi Uusivirta, a Finnish singer, at a Helsinki nightlclub. A Finnish magazine, Seiska, said the pair may also have kissed, but Ms Marin disputes the claim and Mr. Uusivirta wrote on Instagram that “we are friends and nothing inappropriate has happened. I won’t comment on the matter anymore publicly.”

Could the politically damaging videos be another edition of Kremlin-manufactured kompromat? Moscow could not have made the actual videos, and Ms. Marin herself has defended her actions as a young leader who was simply enjoying some leisure time among friends: “It should be accepted that even decision-makers are dancing, singing and partying,” she told a Finnish newspaper. 

But the timing is suspect. As the AP reported, the video was posted online “after Finland on Wednesday decided to limit the number of visas issued to Russians beginning September 1, amid a rush of Russian tourists bound for Europe.” Normally there are about a thousand visa application appointments in Russia each day, according to the Finnish government, but soon that number will be restricted to 500 a day.

Mr. Järvinen, the IT expert, did not have proof of Russian involvement, and he also proffered that someone might be “so stupid that they filmed something like this at the prime minister’s party and put it on social media.”

He also said that “Finland’s credibility could suffer if the videos that spread about Marin were shown on international — and especially Russian television news,” and that there is a risk that “the Russians could manipulate the videos in the future if more of them are leaked to the public.”

To say that Russian president Vladimir Putin takes a dim view of Finland’s recently planned accession to NATO is an understatement, and any discord in Finnish politics ahead of that development would be seen by Mr. Putin as a feather in the Kremlin’s cap.

The Finns have largely stood by Ms. Marin so far in the scandal, with Finnish women even posting videos on social media of themselves dancing to show their support. But the leak of two videos in such short succession means there might be more.

Mr. Järvinen put it bluntly: “There could be something really dangerous in the next video.”