Footage shows Zadie O’Connell, 24, sexually assaulting a commuter and threatening other passengers on a train from London to Essex last month.
British Transport Police tonight said the 24-year-old was later arrested on suspicion of two counts of sexual assault and four counts of common assault.
O'Connell's social media accounts reveal she bragged last month of having "p***ed in a mates garden" and of being fined for vomiting in the back of a taxi.
In late October she tweeted: "How the f*** have I just got home and managed to get an £80 charge for throwing up in the cab lmao. I f***ing hate me."