The shooting was reported at about 5:15 p.m. in a residence at 309 Imperial Beach Boulevard, said Lt. Kenn Nelson of the San Diego County Sheriff's Department.
"The caller said while at home he heard two gunshots come from an upstairs bedroom, which was shared by two of his roommates," Nelson said. "When he went to investigate, he found both of them lying on the floor with obvious signs of trauma to their upper bodies."
Arriving officers found the woman dead at the scene but the man was taken to a hospital where he later died, the lieutenant said.
"There are believed to be no outstanding suspects at this time," Nelson said.