Pasechnik's father worked in law enforcement, for the OBKhSS, for 26 years. In 1975 the Pasechnik family moved to Magadan in the Russian Far East where Pasechnik's father was associated with gold mine operations. Pasechnik graduated the Donetsk Military-Political College and worked for the Security Service of Ukraine in Luhansk Oblast as a chief of a detachment combating contraband operations and the chief of the Stakhanov district detachment. On 15 August 2006 he became famous for intercepting large quantities of contraband at Izvaryne border checkpoint, at the same time refusing a bribe out of principle. In March 2007 SBU Lieutenant Colonel Pasechnik received from the Ukrainian PresidentViktor Yushchenko a medal For Military Service to Ukraine, "for showing integrity and professionalism in the line of duty". In 2014 he sided with pro-Russian militants, becoming on 9 October 2014 a minister of State Security for the self-proclaimed state Luhansk People's Republic. On 21 November 2017, armed men in unmarked uniforms took up positions in the center of Luhansk in what appeared to be a power struggle between the head of the republic Igor Plotnitsky and the LPR appointed interior ministerIgor Kornet. Three days later the website of the separatists stated that Plotnitsky had resigned "for health reasons. Multiple war wounds, the effects of blast injuries, took their toll." The website stated that Pasechnik had been named acting leader "until the next elections." Russian media reported that Plotnitsky had fled the unrecognised republic on 23 November 2017 to Russia. On 25 November the 38-member People's Council of the LPR unanimously approved Plotnitsky's resignation. Pasechnik declared his adherence to the Minsk accords, claiming "The republic will be consistently executing the obligations taken under these agreements." On 30 March 2018 Pasechnik stated "Our experience can help all regions of Ukraine eventually gain freedom and independence, and then we can together declare a new Ukraine in which representatives of different nationalities and cultures will freely live." Pasechnik stated: "It does not mean, that we will return back into Ukraine. This is the only way to stop this madness, this war. You should understand that we, as a sovereign state will be a state within the state – that will be our special status.”
