Singer Chris Brown has pleaded guilty to assaulting pop star and former girlfriend Rihanna. Brown was sentenced to five years probation and six months of community service - cleaning up graffiti and roadsweeping. Los Angeles Superior Court Judge Patricia Schnegg also imposed a court order requiring Brown and Rihanna to stay at least 45 metres from each other, except at industry events when the distance is reduced to nine metres. Brown's plea to a felony charge will subject him to substantial scrutiny by probation officials, and the judge's order rules out any short-term prospects for reconciliation. Mark Geragos, Brown's lawyer, said the plea represented the singer taking responsibility for his actions - which included beating, choking and biting Rihanna during a fight early on February 8, according to police. Brown was arrested in February, hours after police say he hit and threatened Rihanna after leaving a pre-Grammy party.