A fourth suspect is in custody in the Ohio forced labor case after 21-year-old Dezerah Silsby turned herself into police. The four suspects supposedly held a mentally disabled woman and her daughter captive in a basement with free-roaming animals, CNN reported on Wednesday. Silsby is expected to appear in court on Thursday afternoon.

According to officials, Jordie Callahan, 26, Jessica Hunt, 31, and Daniel Brown, 33, have already been arrested and charged with forced labor.

The victims were held captive for more than a year in a crowded apartment, where the woman was allegedly forced to do manual labor and threatened with dogs and snakes, police said.

Federal prosecutors maintain the woman was being held captive so the suspects could collect her government benefits and beat her so they could steal her painkillers. The victims were also apparently kept with a roaming iguana, and the lizard was fed better fed than they were.

"The living conditions were simply subhuman," said Steven Dettelbach, U.S. attorney for the Northern District of Ohio, according to CNN. FBI Special Agent Eric Smith told reporters on Tuesday that the victims weren't allowed to use the bathroom at times.

Meanwhile, Callahan’s defense attorney Andy Hyde maintains that the women were all friends and no one was forced to do anything. "It was clear in my discussions that they were never forced. This group were all friends," Hyde told CNN. "There are photographs ... [of] them all drinking beer together, laughing, joking on a couch. Traveling to other places together. They moved to several different residences together."