Russia has complained to Finland about vandalism at a Russian consulate on the Aland islands in the Baltic Sea between Finland and Sweden, the Finnish foreign ministry said on Thursday.
The Russian foreign ministry said on Wednesday a group of people had thrown "an explosive noise device" and other items into the consulate's territory, causing material damage to the building between April 20 and May 1.
"The perpetrators' actions posed a direct threat to the life and health of the staff of the Russian mission," it said.
Local police said they had initiated a preliminary investigation into the case, adding they had the identities of persons who may have been involved.
"The damage consists of the consulate's mailbox being torn down from its stand and a beer bottle being thrown at the consulate, resulting in a window panel being broken," it said in a statement.
The Finnish foreign ministry said police were "clarifying and investigating" the incident. "The case is regrettable," it said in an email.
Aland's demilitarised status, which dates back to the end of the Crimean war in 1856, and Russia's consular presence in the autonomous region have become a topic of debate in Finland after neighbouring Russia initiated its full-scale invasion of Ukraine last year.
(Reporting by Anne Kauranen in Helsinki, additional reporting by Caleb Davis in Gdansk, editing by Terje Solsvik, Anna Ringstrom and Nick Macfie)