We report the first Kerr-lens mode-locked polycrystalline Cr^2+:ZnS and Cr^2+:ZnSe lasers, with pulse duration of 125 fs at a pulse repetition rate of 160 MHz, emitting around 2.3 – 2.4 µm. The mode-locked lasers were pumped by a radiation of 1550 nm Er-fiber amplifier seeded by semiconductor laser. The long-term stable Kerr-lens mode-locked laser operation with the output power of 30 mW (Cr^2+:ZnS) and 60 mW (Cr^2+:ZnSe) was obtained. We also demonstrate amplification of the fs laser pulse train in a cw pumped single-pass polycrystalline Cr^2+:ZnS laser amplifier.