Wikipedia
Maslenki
The Maslenki incident, was an attack by Soviet NKVD troops on 15 June 1940 against the Latvian border posts in district of Abrene at the then USSR/Latvian Republic border on the eve of Soviet occupation of Latvia.
The incident, though mainly known by the name of "Maslenki" ("Masļenki" in Latvian) border post, in fact consisted of three separate nearly simultaneously launched attacks on Latvian border posts by Soviet forces at the early dawn of June 15, 1940. Two border posts were actually attacked and another commenced attack was canceled. As a result, 3 border guards and 2 civilians (incl. one child) were killed, 37 were kidnapped and brought to USSR as hostages.