Finland is to expel nine employees from the Russian embassy in Helsinki, according to the Finnish Security Intelligence Service (Supo).
In a tweet early on Tuesday evening, the security agency suggested that the Russians in question had been working on intelligence missions in Finland.
"This is a significant setback for Russian intelligence in Finland, and corresponds to the Finnish Security Intelligence Service's counter-espionage goals," the agency stated in the tweet posted at 5:28pm on Tuesday.
The Ministry for Foreign Affairs will inform the Russian ambassador about the matter, according to a government press release.
The matter was decided by the Finnish government's foreign and security policy ministerial committee (TP-UTVA) and President Sauli Niinistö, according to the government.
A president's office statement said the Russian embassy workers' actions were in violation of the Vienna Convention on diplomatic relations.
Edited at 19:09 to add clarity and details.
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