[HIGHLIGHTS] "Suspicious" mail arrives at the Embassy of Finland in Russia, Moscow comments on the incident

The Finnish embassy in Moscow announced on Friday that it had received three letters that arrived at the diplomatic mission building. One of the letters contained powder, and the embassy communicated with the Russian Foreign Ministry about them.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'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.