A month-long observation of two horizontal mutually light-isolated scintillating screens, 1 m2 in area and located one above the other a certain distance apart, revealed about 15 correlated signals, whose time shift corresponds to an average velocity of only ∼10-15 km s−1. We assign the origin of these signals to the negative daemons, i.e. electrically charged Planckian particles which supposedly form the DM in the Galactic disc, captured into the near- Earth orbits. As follows from an analysis of the factors accompanying the signals and governing their properties, the key part in the detection of daemons is played apparently by two processes: (i) nucleon decay in the daemon-containing nucleus, and (ii) emission of energetic electrons and nucleons in the capture of a nucleus of atom by a daemon. The first process results in the release by daemons of the heavy nuclei captured by them in traversing the components of the system (S, Fe, Zn, Sn etc.), and the second, in excitation of the main part of the scintillations observed in the ZnS(Ag) phosphor. The flux of slow daemons through the Earth's surface estimated from the measurements is ∼10−9 cm−2 s−1.