A high school bus driver in Yuma has been arrested on suspicion of having an ongoing sexual relationship with a 15-year-old student.

The Yuma County Sheriff's Office said Friday that Sixto Rocabado Jr., 31, was arrested Wednesday after the parents of the female student reported that he had left inappropriate messages on the girl's MySpace.com page.

Sheriff's spokesman Capt. Eben Bratcher says investigators learned that Rocabado was the girl's school bus driver and had allegedly had sexual contact with her over the last few weeks.

Rocabado was arrested on suspicion of aggravated assault, custodial interference, kidnapping, sexual abuse and sexual assault.

He is being held in the Yuma County jail on a $239,265 bond.