The woman's roommate called 911 shortly after 10:30 p.m. Tuesday and told dispatchers she was unconscious and had suffered some type of trauma to her upper body. Deputies and paramedics sent to the home on Mission Greens Road near Mission Gorge Road arrived to find her dead, sheriff's Lt. Kenneth Nelson said.
"Based on the circumstances surrounding the incident, detectives are investigating the case as a possible homicide," he said.
A cause-of-death ruling was on hold pending an autopsy, according to the lieutenant. The woman's name was not immediately released.
Deputies interviewed witnesses and obtained a warrant to search the residence, Nelson told reporters at a morning briefing.
Anyone with information on the case was asked to call the sheriff's department at 858-974-2321 or after business hours at 858-565-5200. Anonymous tips can be submitted by calling Crime Stoppers at 888-580-8477.