Brea police arrested Michael James Jackson at his home following a year-long investigation.
The 52-year-old faces eight felony charges, including three counts of sexual penetration by means of fraudulent representation of professional purpose, sexual penetration by foreign object and force, sexual battery by fraud, sexual battery by foreign object of unconscious victim, forcible rape and possession of child pornography.
Last October, a 38-year-old Brea woman told police that Jackson had touched her inappropriately during a massage at her home.
Detectives say they later identified two more victims - a 31-year-old woman from Huntington Beach who was allegedly assaulted in 2012 and a 48-year-old woman from Newport Beach who was allegedly assaulted in 2000.
Investigators also discovered child pornography on Jackson's computer during a search of his home last December.
Jackson is being held in Orange County jail on $1 million bail.
Police believe there may be additional victims who have yet to come forward. Jackson operated his massage business under the name "On the Spot Therapy." If you have any information about these assaults or you believe you were a victim of Jackson, you're urged to contact Detective Debbie Stark with the Brea Police Department at (714) 990-7638.