FULLERTON – A man suspected of planting spyware on dozens of computers in order to take control of laptop webcams and photograph women in their homes was arrested Wednesday at his Fullerton residence, police said.

Investigators carried out an arrest warrant for Trevor Harwell, 20, who they suspect of using his position with Rezitech Inc., a computer service company, to install software allowing him to remotely access victims’ computers, Fullerton police Sgt. Andrew Goodrich said.

“Once he had access, he would take photographs of the users, usually women,” Goodrich said. “Often, the female victims were undressed or changing clothes. Harwell then stored the photos on a remote server, and eventually downloaded them on his own computer.”

Investigators discovered “numerous” victims, Goodrich said, all of whom are adult women.

Authorities say Harwell worked on computers in both Orange and Los Angeles counties. Investigators seized hundreds of thousands of still images and videos from his computer, Goodrich said.

Authorities began their investigation in summer 2010 after a Fullerton resident noticed that suspicious messages were popping up on their daughter’s computer.

Goodrich said the messages told users to “fix their internal sensor soon,” advising them that if they were unsure of what to do, they could “try putting your laptop near hot steam for several minutes to clean the sensor.” The message convinced some of the victims to take their laptops in the bathroom with them as they showered, Goodrich said.

Along with the spyware, investigators believe that Harwell may have exploited Macintosh computers connected to Biola University’s internal network. Harwell is a former student at the school, which many of the victims attended, Goodrich said.

There was no evidence that Harwell shared the photos with anyone else or posted them online, Goodrich said.

Harwell was released from custody after posting a $50,000 bond on Wednesday afternoon. According Orange County Superior Court records, he is facing 12 felony counts of computer access and fraud.

Additional charges will likely be filed in Los Angeles County, Goodrich said, although the cases could be combined at a later date.

“This is a very chilling and troubling kind of crime, when people’s privacy is violated like this,” Goodrich said. “It goes to a lot of people’s deep fears of being watched and not having privacy in their own homes.”

Police haven’t ruled out the possibility of other potential victims, asking people who think they may have been affected to check their “/Library/WebServer/Documents” directory for “Camcapture,” a program that Harwell is suspected of installing in the computers in order to access them.

Investigators are asking anyone who believes they were a victim to call their local police department or Fullerton police detective Kathryn Hamel at 714-738-5327.

Contact the writer: 714-796-7939 or semery@ocregister.com