West Yorkshire Police today released details of the incident along with a CCTV image of a man they want to trace.
The assault took place just off Firth Street at around 6.30am on Tuesday.
A spokesman said: "The 19-year-old female victim was walking through a car park towards the footbridge nearby and she was approached by the male suspect.
"He grabbed her but let go after she pushed him away and he fled across the nearby footbridge."
The suspect was described as a large, Asian man in his mid to late 40s and approximately 5ft 5in.
He had a small amount of stubble on his face and spoke in broken English with a strong Asian accent.
Anyone with any information about the incident or who recognises the man pictured in the photo is asked to contact the police via 101, quoting crime reference 13170590560.
Information can also be passed on via the independent charity Crimestoppers on 0800 555 111.