A man who used to drive for both Uber and Lyft has been accused of sexually assaulting several women who hailed rides on the platforms, and investigators believe there are likely more victims that have yet to come forward.

One woman, an 18-year-old college student, reported an assault that allegedly happened on Friday afternoon after she’d requested an Uber car in a city near San Diego, reports the Associated Press. She told police that the driver picked her up on campus, and immediately turned off the Uber app.

That tipped her off that something was wrong, and she texted her friends that she felt uncomfortable. He then drove her to another location and attacked her inside his minivan, police say. He was arrested later that day at his home.

During the course of the investigation, detectives said they discovered more victims, including two 19-year-old women in a city nearby. The suspect had given one of them a Lyft ride on Sept. 7, while the other was waiting at the destination. He asked to take a photo with the two women, and allegedly touched them inappropriately while posing.

Another student reported on Sept. 6 that though she hadn’t summoned a ride, the suspect tried to lure her into his vehicle, but she refused. Police determined no crime had occurred but told the man he had to stay away from the college.

The 37-year-old suspect pleaded not guilty on Wednesday to multiple sexual assault charges. Both Lyft and Uber removed him from their platforms, but it’s unclear when, or when they were contacted about the recent assaults.

Police are now asking other victims to come forward.

“We’re asking you to find the courage to come forward so we can hold Vague accountable for his actions,” an Escondido police lieutenant said.

The AP notes that the suspect pleaded guilty to a misdemeanor charge of vehicle burglary linked to a July 2012 incident, but neither company responded to emails from the AP asking whether they were aware of his record, or if it would have kept him from driving on their platforms in the first place.

Lyft says it has “a strict zero-tolerance policy for any type of violent behavior, abuse or harassment and we have permanently deactivated the driver’s access to the platform. Drivers on the Lyft platform undergo a thorough criminal background check across local, state and federal databases that go back in time to the maximum extent allowable by law.”

As for Uber, the company said in a statement that “there is no excuse for the violent acts described and reported to police. We are working with law enforcement officials to fully support their investigation, and the driver has been banned from accessing the Uber app.”

There’s a bill awaiting Gov. Jerry Brown’s signature that would require stricter background checks for ride-hail drivers, and would ban companies from hiring drivers who are registered sex offenders, have been convicted of violent felonies, or have been convicted of driving while intoxicated in the past seven years.

Former Uber, Lyft driver charged with assaulting passengers [Associated Press]

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