Two registered sex offenders have been arrested in connection with the deaths of four women in Orange County, California.

Franc Cano, 27, and Steven Dean Gordon, 45, were arrested Friday in Anaheim. The LA Times reports both men were sex offenders and were required to wear electronic monitoring. The two had cut their monitoring bracelets and fled to Nevada in 2012 but were later captured. Since returning to California, they now have to check in with police every 30 days.

According to reports, the suspects were wearing their required GPS monitoring devices at the time of the alleged attacks.

A murder investigation began when the naked body of 21-year old Jarrae Estepp was discovered last month on a conveyor belt at an Anaheim recycling center. Estepp had been seen in an area of the city known for prostitution. 

Estepp moved to California from Oklahoma City. She had been featured in a series of undercover videos on prostitution titled “JohnTV.” According to the group’s website, their efforts are intended to “cast a spotlight on the graphic realities of street prostitution, exposethe perpetrators, dispel the myths and move the social conscioustowards a more realistic awareness.” In one video shot by the group in January 2012, Estepp–who went by the name Sarah–can be seen walking the streets while heavily pregnant.

No Boundaries International, an Oklahoma City group which reaches out to women involved in prostitution and sex trafficking, held a candlelight vigil for Estepp last month. NBI’s president Lori Basley told the LA Times last month: “Nobody is designed to be sold over and over throughout the day, toexperience the violence and consequences these girls end upexperiencing.”

The other three women who Cano and Gordon are accused of killing also had police records involving prostitution. Kianna Jackson, 20, disappeared last October. Monique Vargas, 34, vanished three weeks later. The LA Times reports that after she disappeared, her mother walked some of the rougher parts of Santa Ana asking drug dealers and prostitutes if they knew what had happened to her daughter. Martha Anaya, 28, disappeared in mid-November as she was preparing for her daughter’s birthday party.

Police have scheduled a press conference for today, at which they are expected to reveal more about the evidence they used to connect the two men to the murders. CBS LA reports that the police are reaching out to other law enforcement agencies across California and around the country to determine whether the two men might be connected to any similar murder cases.