Joan Watson was found dead just before 9:30 a.m. inside her apartment at 3118 W. Sylvania Ave.
The caller told police that she found a woman naked and "mutilated." She was pronounced dead at 9:32 a.m.
Police charged the suspect, James M. Day, 46, with murder. His address was not immediately available.
A man who answered the phone for the company who owns the apartment building said he had no information about what occurred and disconnected the call.
An autopsy for Ms. Watson is scheduled for Monday.