Aarion Teri Lee Mosley, of Gary, Ind., faces multiple counts of rape, robbery and criminal deviate conduct. He is in custody at the Lake County Jail.
Officials say the 68-year-old victim was seeking shelter from the rain at the train station when Mosley approached her with a handgun. Cameras at the station caught the offender riding away on a bicycle.
Mosley was arrested Monday at Gary's Lew Wallace High school. Police say they have recovered a BB gun, bicycle and clothing worn during the crime. The DNA analysis is pending.