A 22-year-old man was arrested on suspicion of an assault on two teenagers and a policeman at Wimbledon station on Saturday night.
Police were called to the scene just before 11pm and arrested the man on suspicion of being drunk and disorderly, sexual assault, wounding and assaulting a policeman.
The teenage couple, both 16-years-old, were on a night out when the alleged assault took place.
The suspect has been bailed until February 25 while police investigate.
Anyone who witnessed the incident should contact British Transport Police on 0800 405040, quoting crime reference number 594, January 25 2014.
- What to do if you've got an Ikea chest of drawers that isn't fixed to the wall
- Sadiq Khan demands more devolution for London in Brexit aftermath
- WEATHER: South London and north Surrey set for another day of underwhelming weather
- Matthew Kitandwe murder: Second boy arrested as detectives return to the scene one week on and £10,000 reward for information is offered
- Police hunting man wanted in connection to five burglaries