Norwich — A Norwich man with a prior sexual assault conviction involving a 6-year-old boy was charged again Friday with sexually assaulting a minor, police said.  

Robert F. O'Donnell, 48, who is in the custody of the Corrigan-Radgowski Correctional Center, was charged with first-degree sexual assault, second-degree sexual assault and risk of injury to a minor.

Norwich police said Sunday they were alerted about possible abuse and neglect of a minor through the Department of Children and Family Services last December. A child victim, police said, had accused O'Donnell of sexual assault and sexual contact.

O'Donnell was placed at Corrigan in late December after he was charged with violating a restraining order and could not post a $350,000 bond. Since that time, police obtained a warrant for his arrest on the new charges and he was arraigned Friday in Norwich Superior Court.

O'Donnell was originally convicted in 1998 of sexually assaulting a 6-year-old boy and served 4 1/2 years in prison. In addition, he was required to register as a sex offender for life.

Beginning in 2002, O'Donnell violated his probation four times over the next six years including using a MySpace account to attract others interested in children. In 2008 he was sentenced to two years in prison for violating his probation.