We investigated the temperature and magnetic field dependence of the Hall effect, the magnetization and the resistivity of Mn-doped β-FeSi ₂ single crystals in the temperature range of 4-300 K in magnetic fields up to 5 T. A negative magnetoresistance as well as strong nonlinear magnetic field dependence of the Hall resistivity and magnetization were observed. The anomalous contribution to the Hall resistivity is found to be important. We also observed the value of the anomalous Hall coefficient to increase with decreasing temperature as the square of the resistivity. It was shown that the magnetization of Mn-doped samples cooled in zero-external field and in a field are different. This resembles the properties of spin glasses. The dominant scattering mechanisms are determined by analyzing the Hall mobility data. The value of the valence band deformation potential is estimated. A particularly important role is played by the anomalous Hall effect which is the microscopic mechanism involving the spin dependent scattering on Mn ions and spin-orbit coupling in the Mn-doped β-FeSi ₂ single crystals.