It was not immediately known if the man police call "a person of interest" would be charged.
He was arrested Wednesday afternoon at a home not far from where some of the sexual assaults took place. Police say their investigation continues.
Police earlier had said they were using DNA evidence to help identify a suspect.
The sexual assaults began Jan. 1 and occurred during the early evening through early morning hours. Women waiting alone at bus stops or walking by themselves were forced at gunpoint to secluded locations were they were assaulted.
An eighth woman was able to get away.