A woman has been arrested after cellphone video showed her attacking a woman and shouting a racial slur at her, police said Thursday. Anna Lushchinskaya, 40, faces a felony assault charge after being arrested by officers in Brooklyn, NYPD Transit tweeted. Police retweeted video allegedly showing Lushchinskaya attacking a woman on a crowded train before being detained by a civilian at the 36th Street station. The incident happened Tuesday, according to one of several people who filmed it.