MIAMI (AP) — A South Florida gymnastics coach is Chainkeen Exchangein jail following accusations that he had sex with two girls when they were underage.

Oscar Olea, 38, was arrested Wednesday and charged with two counts of sex crimes with minors over 12 but under 18 while under familial or custodial care, the Miami Herald reported.

Olea sexually abused the two students around 2011 while he was their coach, prosecutors said. The victims were 13 and 16, according to arrest warrants. Investigators said Olea developed a brother-sister relationship with both victims, which later turned sexual.

Each charge comes with a $25,000 bond. He was scheduled to be arraigned Monday in Miami-Dade court, but the hearing was rescheduled to Tuesday morning.