A 34-year-old Virginia man pled guilty to physically and sexually assaulting a child on a Greyhound bus and assaulting an officer in an unrelated incident on the same day last September.

Donato Richardson of Roanoke, Va., admitted that he boarded a Greyhound bus in Washington D.C. en route to Richmond at about 2 a.m. on Sept. 19, 2012, when he leaned over to a 10-year-old boy sitting alone and sexually assaulted him. The boy's mother was also on the bus, sitting on the opposite side two rows behind.

The boy pushed Richardson's hand away and told him to stop, and Richardson then grabbed the boy. When another passenger noticed the commotion, Richardson escaped the bus via the emergency exit.

Earlier that day in an unrelated incident, Richardson was in downtown D.C. harassing pedestrians and security officers for the Department of Justice approached him about his behavior. He fled, but officers caught up with him and tried to contain him. Richardson assaulted one of the officers -- a special duty U.S. Marshal -- and was placed under arrest.

Richardson faces up to five years in prison for the sexual abuse and up to 180 days in jail for each of the other charges. He will also be required to register as a sex offender for 10 years.