Officers arrested Corrections Officer Leon Scott, 34, at 9:20 p.m. Friday. His 24-year-old, unemployed brother, Anthony Kniffin, was taken into custody at 2:30 a.m. Saturday.
Both men were identified by the victims, and each confessed to having sexual conduct with them, according to a police report. Scott has been employed as a corrections officer at Arizona State Prison in Florence, according to Department of Corrections Spokesman Barrett Marson.
Scott and Kniffin both confessed that three separate sexual encounters with the girls took place in June and July, according to a report.
Both men admitted knowing the girls were underage, but said they did not believe the girls when they initially told them their ages. Police documents indicated both men were present during the discussion of one of the victims' planned sweet 16 party.
All three of the encounters reportedly took place in the men's apartment, police reported. The victims' mother had previously had a brief relationship with Kniffin's brother, police said.
According to Sgt. Ed Wessing, spokesman for Mesa Police, the mother of one of the victims learned of the sexual conduct through a post on her daughter's Facebook profile.