Prosecutors have expanded their investigation into alleged rape by a California surgeon and are looking into alleged crimes that could have occurred over the last 20 years, the Orange County district attorney said Friday.

In a news conference, District Attorney Tony Rackauckas said prosecutors have received more than 50 calls about the case and have established more than 12 “credible potential victims” who have come forward with allegations against Grant Robicheaux, 38, and his girlfriend Cerissa Riley, 31.

Prosecutors have said the couple used their good looks and charm to drug and rape at least two women.

“As to Robicheaux, we are examining crimes that may have taken place from two decades ago to the present day,” Rackauckas said, adding, “We’re expanding our inquiry to several states, as well as to other parts of California.”

Asked if the investigation could encompass Robicheaux’s time in college and in medical school, Rackauckas said, “Yes.”

At least one male has come forward as an alleged victim, according to prosecutors.

Rackauckas said the alleged crimes are not limited to Newport Beach, where at least one woman has said she met Riley and Robicheaux at a restaurant in April 2016, before becoming intoxicated and going back to Robicheaux’s apartment, where she was allegedly drugged and raped by the couple, according to prosecutors.

It’s also possible, Rackauckas said, that Robicheaux and Riley didn’t just meet their “prey” in person, but that Robicheaux might have met some through dating apps like Tinder and Bumble.

“Ladies, please be careful when you meet people on these apps,” Rackauckas said. “You do’t know what is behind what appears to be a perfect smile.”

Authorities continue to ask potential victims to come forward and share what they may know with prosecutors.

“No one gets a pass to have their way with you once you are unconscious or past the point of consent,” Rackauckas said.

Suspects deny the accusations

Robicheaux and Riley been charged with rape by use of drugs, oral copulation by anesthesia or controlled substance, assault with intent to commit sexual offense, and possession of a controlled substance for sale. Robicheaux is also accused of firearms violations.

They each paid $100,000 bail last week when they were arrested. They will be arraigned on October 25.

Attorneys for Riley and Robicheaux have previously issued a joint statement denying the allegations.

“They have been aware of these accusations for a number of months, and each of them will formally deny the truth of these allegations at their first opportunity in court,” the attorneys said of their clients.

“Dr. Robicheaux and Ms. Riley believe that such allegations do a disservice to, and dangerously undermine, the true victims of sexual assault, and they are eager to have the proper spotlight shed on this case in a public trial.”

In 2014, Robicheaux appeared on an episode of Bravo’s “Online Dating Rituals of the American Male.”

How the alleged attacks unfolded

Investigators believe Riley approached the women at a bar or restaurant, then invited her boyfriend over, Rackauckas said Tuesday.

He said Riley and Robicheaux met one 32-year-old woman rackauckat a restaurant in Newport Beach in April 2016. On another occasion, they invited her to a party and took her back to his apartment once she was intoxicated, Rackauckas said.

Afterward, they drugged and raped the woman, the district attorney said. He said the incident was recorded on video.

Six months later, prosecutors say, another woman alleged the couple sexually assaulted her at the apartment after she got drunk at a bar with them.

Investigators found hundreds of clips of women in various states of consciousness on the surgeon’s phone, Rackauckas said. Many of them appeared unable to consent to sexual contact, and many videos included Riley. He did not say whether the same women were seen in multiple clips.

“Based on this evidence, we believe that there might be many unidentified victims out there,” he said.