An Oregon man allegedly used social media to meet single mothers with young daughters, then sexually assaulted the women and children, authorities said.

Antonio Arredondo, 37, has been charged with three counts of rape, two counts of sodomy and four counts of sex abuse in four cases in Oregon, and investigators believe there may be more potential victims, according to a joint press release from multiple law enforcement agencies in the state.

Sgt. Danny DiPietro of the Washington County Sheriff’s Office told NBC affiliate KGW News that Arredondo allegedly targeted single mothers who were seeking romantic relationships on social media apps such as Facebook and had disclosed that they had daughters.

“These women were probably trying to be upfront, trying to have a dating life and say, ‘Hey, I have children, if that’s not OK with you, we’re not a good match,’” DiPietro told KGW.

According to investigators, after some time passed in the relationships, Arredondo would be invited into the victims’ homes, where he eventually sexually assaulted either the mother or daughter or both, the press release stated.

A grand jury indicted Arredondo on Aug. 2 in connection with a case in Tigard, Oregon. Another indictment followed on Aug. 14 in connection with another case in the same county. While investigating those cases, authorities said they learned of two other cases in which Arredondo was under investigation for similar allegations: one in Portland and another in Dallas, Oregon.

According to authorities, Arredondo has lived in Oregon for several years and was required to register as a sex offender based on a previous conviction in Texas. Public records show he was convicted in 2009 of indecency with a child in Texas. His name does not appear on Oregon’s online sex offender registry, which only lists Level 3 offenders, considered the highest risk category.

Authorities released a photo of Arredondo to help potential victims identify him; anyone with pertinent information can contact their local law enforcement agency or the Washington County Sheriff’s Office.

According to Fox News, Arredondo has pleaded not guilty to all charges against him. His next court date is scheduled for Tuesday.

Need help? Visit RAINN’s National Sexual Assault Online Hotline or the National Sexual Violence Resource Center’s website.