The alleged incident took place when the complainant boarded a train at Lower Parel. (Representational)

A 35-year-old woman was allegedly assaulted and bitten by a fellow woman commuter during a fight in a local train on Mumbai's Western Railway line, police said on Thursday.

While the Government Railway Police (GRP) have registered a case, the accused woman is yet to be identified.

The alleged incident took place when Nazrana Pille, the complainant, boarded a local train at Lower Parel on Monday.

"While I was trying to board the train, this lady was standing at the door, blocking entry. As the ladies compartment was crowded, she received a small nudge from me while boarding," Ms Pille told news agency PTI.

"She jabbed me in the ribcage. When I requested her to stop being violent, she started abusing me. I asked her to get down at Dadar and approach the police and lodge a complaint. Then she again lost her cool, assaulted me and even bit me on my left arm," Ms Pille claimed.

"Incidents like these, where women commuters become violent, are increasing over the last few months," she said.

Ms Pille also claimed that she lost jewellery worth Rs 9,000 during the incident.

The accused woman allegedly got down and ran away at Mahim station, but before that Ms Pille managed to click her picture on her phone, she said.

Ms Pille then filed a complaint with the Bandra GRP.

"We have registered FIR (First Information Report) against an unidentified woman under Indian Penal Code sections 323 (assault) and 504 (intentional insult with intent to provoke breach of peace). The woman is yet to be identified," a GRP official said.