DC conductivity measurements on thin films of a-Se80In20-xPbx (where x = 0, 2, 6 and 10) are reported in the temperature range 200-400 K. The density of states near the Fermi level is calculated using the DC conductivity (Mott parameters). The conduction in the low-temperature region is found to be due to variable range hopping while that in the high-temperature region is due to thermally assisted tunneling of the carriers in the localized states near the band edge. (C) 2002 Elsevier Science B.V. All rights reserved.