police investigating the case have come across cctv that shows the man following three other potential victims earlier on the same night .
the 18-year-old was hit over the head 20 times with a rock and dragged into a garden to be brutally raped by the man and left for dead in the beeston area of leeds last month .
he was shown wearing a green puma sweatshirt , dark jacket and jeans in the city centre as she walked past a row of bars .