The accident occurred when the empty muckskip was lowering from surface into the shaft bottom placed on a flat car, after that the workers removed lock plate from both side of muckskip, when the gantry crane lift up, During lift up of the muckskip, one of lock plate on east side had moved back into muckskip hook, Thereby causing a jerk and getting swing of lift beam and then hitting the cables. The crane operator quickly applied the break and further movement of crane was stopped. The tunnel supervisor/ engineer were informed about the incident and necessary steps were taken to repaired the cables. Normal activities resumed in about 4:00 AM