The Finnish embassy in Moscow announced on Friday that it had received three letters that arrived at the diplomatic mission building, one of which contained powder, and the embassy communicated with the Russian Foreign Ministry about them.
Russian Foreign Ministry spokeswoman Maria Zakharova said Friday in response to the incident that the Finnish embassy in Moscow had already received a letter containing unknown powder and had informed Russian authorities.
Relations between Moscow and Helsinki have deteriorated sharply since Finland formally joined NATO on April 4, becoming the thirty-first member of the U.S.-led military alliance. Finland shares a long land border with Russia.
Zakharova said the embassy told the Russian Foreign Ministry it had received three letters on Thursday, at least one of which contained powder.
"We can confirm that the Embassy of Finland has issued an appeal to the Russian Foreign Ministry to hand over three identical envelopes addressed to the military attaché and his aides on April 13 to the mailbox of the diplomatic mission," she said. The results of the investigation will be communicated to the Embassy of Finland."
Finland's decision to join NATO ended seven decades of strategic non-alignment that began after the country repelled an attempt at a Soviet invasion during World War Two. In the postwar period, Helsinki chose to maintain friendly relations with Moscow.
But the Ukraine war in February 2022 prompted Finns to seek security under NATO's collective defense agreement, which states that an attack on one member is an attack on all member states.