Police said the woman was waiting for a train at 8.30pm on Sunday on platform two when she was approached by a man who began talking to her.

He then punched and kicked her before dragging her to the ground.

The woman managed to run off into the nearby underpass where the man caught up with her and physically assaulted her again before subjecting her to a serious sexual assault.

After the attack the victim ran back to platform two where her train had arrived and reported the incident to train staff. One of the train staff shouted at the suspect but he ran off.

The suspect has been described as aged in his 40s and having an olive or dark European complexion. He was of medium build, about 5ft 7in, with very short or shaved dark hair. He was said to be wearing a light coloured, short jacket and dark trousers, which were possibly jeans. He was also described as carrying a large, clear plastic bag.

The victim suffered cuts and bruising in the attack and was very shaken by her ordeal. She is being helped by specially trained police officers.

Det Insp Dave Boldison, of British Transport Police, said: "This was a vicious attack on a young woman and we are determined to find the man responsible.

"I am appealing to members of the public who may have information which could help with our enquiry, to contact us as a matter of urgency. The suspect was said to be carrying a large, clear plastic bag. This is quite an unusual and distinctive feature. Were you in the area around Wakefield Kirkgate railway station yesterday evening? Did you see someone matching the suspect's description?

"I would also like to reassure the public that these types of incidents are rare on the railway network and that British Transport Police has a team of specialist officers rigorously investigating this matter. Extra reassurance patrols have also been mounted."

Anyone with information should contact British Transport Police on Freephone 0800 405040 quoting incident number 458 of 12/10/08 or call Crimestoppers on 0800 555 111.