The man, whose identity was not released, was arrested in connection with the Baseline Killer attacks, one of two serial killing sprees that have terrorized the Phoenix area in recent months, said Sgt. Andy Hill, a Phoenix Police Department spokesman.
Reports show the sexual assaults have ranged from fondling to rape. In many cases, victims had conversations with the man before they were attacked. He appears to always have a gun, and often threatens to shoot and kill victims.
In the other recent killings, dubbed the "Serial Shooter" case, police arrested two men last month in investigation of more than a dozen shootings, seven fatal. They have been charged in two fatal shootings.
Police believe the men - Dale S. Hausner, 33, and Samuel John Dieteman, 30 - took turns shooting random victims late at night and early in the morning. Both men have pleaded not guilty.
In a jailhouse interview last month, Hausner said he is innocent but it is possible his roommate, Dieteman, is responsible for the shootings. Dieteman, a Minnesota native, refused interview requests.