AURORA, Colo. (CBS4) – A man posing as a massage therapist sexually assaulted a 15-year-old girl, Aurora police said, under the guise that he needed to practice massage on the girl to complete his training.

Police arrested Robert Richard Beattie Smith, 28, after he touched the girl inappropriately in her home, police allege.

The teen girl posted on social media that she’d lost her job and was seeking work, police said. Spokeswoman Diana Cooley said the suspect contacted the victim on Craigslist and offered to compensate her in exchange for performing a few hours of massage sessions on her and her 21-year-old sister at the girls’ home.

“She had posted the request for a job,” Cooley told CBS4. “The suspect then contacted her back saying he needed massage practicals and he’d pay her if she’d allow some training time with her.”

Police accuse Smith of assaulting the 15-year-old as the massage session progressed. He then started providing a massage to the older sister, police said, but she objected once the contact became sexual.

“(The teen) felt inappropriate things were going on, but due to the mental state that she was in, she didn’t say anything. When he moved on to her sister, her sister put a stop to it,” Cooley said.

After Smith left the girls called police. With the help of the Aurora Sex Crimes Unit, Smith was arrested two days later on charges of sexual assault on a juvenile and sexual misconduct.

Smith, who lives in Denver, is being held without bond in Arapahoe County Jail. Police said detectives discovered that Smith is wanted in California for a similar offense from July.

“I think like anything else that can be posted on social media, you’ve got to be careful what you post, who you invite into your home, make sure there’s other people with you,” Cooley said.

Police say there could be more victims and are asking anyone with information about Smith to call them at 303-739-6153.