During laying down of liner running tool (total length of Running tool was 12m) onto the cat walk using rig winch from top side and crane with sling from the lower part. A bend on the string was noticed, the string parted from the connection below the running tool. The running tool was at a height around 7m above the cat walk and the lower part length was about 6m. Each part hung and swung above the cat walk area. Catwalk area was clear of personnel. The two parts were laid down separately.