On 18 September 1939, 12 Poles were executed by the Germans in a forest near the Barbara mine in Karviná. Most of them were miners working at the mine. In September 1945, the victims were moved to a common grave in the cemetery in Sucha Średnia (Czech: Prostřední Suchá). The grave bears a plaque with the names of the victims, authored by Bohuslav Man and Adolf Kubiczek. It was founded in 1969 by the works council of the 1 Maja mine in Karviná (formerly Barbara) thanks to the efforts of the son and wife of the murdered miner Jan Mrajca. In addition to the names of those murdered, the plaque bears an inscription in Czech and Polish: "Zde odpočívají bojovníci,/ kteří padli v boji s fašismem ve dnech/ 18.9.1939/ Here rest the fighters/ who died in the fight against fascism/ on 18.9.1939" A memorial in the form of a chapel was erected at the place of execution in the forest next to the mine, on which the names of the murdered are engraved. The author of the monument was Jozef Wątroba.