According to a report by the Berlin-based Correctiv & Der Spiegel [0], it was Russia's 53rd Air Defence Brigade that was directly operating the missile launcher

According to a report by the Berlin-based Correctiv & Der Spiegel [0], it was Russia's 53rd Air Defence Brigade that was directly operating the missile launcher. [0] https://mh17.correctiv.org/english/ https://mh17.correctiv.org/english/