We demonstrate isotope selective ionization of (IBr)-Br-79 and (IBr)-Br-81 isotopologues using field-free alignment induced by a linearly-polarized nanosecond laser pulse with rapid turn off at the maximum. Following the "switched" nanosecond pulse irradiation, a 60-fs laser pulse ionizes one of the isotopologues preferentially. The ion yield ratio I((IBr+)-Br-81)/I((IBr+)-Br-79) varies in the range of 0.93-1.06, depending on time delay between the pulses. This is the first demonstration of laser isotope separation of heavy elements using field-free alignment and angular dependent ionization.