[2] After the outbreak of World War II, he was an aide-de-camp to Colonel Stanisław Szyłejko, commander of the southern section of the defense of Vilnius.

He was interned there on September 18 and placed in a camp, from where he escaped, making his way back to the Vilnius, which was handed over by Soviets to Lithuania on October 29, 1939.

[2] Other significant actions of the unit include: a skirmish with the Germans near the Stracha [be] estate, a clash near Mikoltsy [be], and the disarming of a Wehrmacht garrison in Zhodzhishki [be].

[3][4] The units of the Soviet partisan "Voroshilov" Brigade [be] under the command of Colonel Fedor Markov [ru] also had their encampments in this area.

[3] At that time, the Central Committee of the Communist Party of Byelorussia issued an order to combat Polish partisan units.

[6][7] At the meeting with the command of the Soviet partisans with Burzyński were: 2nd Lt. J. Wiśniewski "Ostroga", 2nd Lt. Zygmunt Niciński "Twardowski" and Sylwester Jachimiak "Chłop".

Markov wrote in his report that he "wanted to avoid a second Katyn," which is why he murdered only 80 Polish soldiers, he also added: "We will cleanse all our regions of this filthy trash.

And the surviving soldiers of "Kmicic" escaped the Soviet partisans and joined the unit formed by Zygmunt Szendzielarz "Łupaszko.

[11] The document, dated November 10, 1943 and signed by Derkachev, who commanded the attack on the Polish camp, includes not only an admission of committing the crime, but also the identification of Soviet Chief of Staff Panteleimon Ponomarenko as the main executive ordering it.

[12] Ponomarenko later, on November 1, 1943, issued a similar order to liquidate the Stolpce battalion of the Home Army, residing in the Naliboki forest in the Novogrudok region.