Homicide Capt. James Clark said Monday that Shakoor Arline, 25, and Lisa Smith, 32, were together in the SUV early Friday when someone opened the rear door and fired nine times, shooting both multiple times in the head.
Maintenance workers found their bodies around 2 p.m. Friday near Lemon Hill Mansion, a historic building in the city's Fairmount Park. Clark said the shootings happened between midnight and 5 a.m.
Arline and Smith met at work at a previous job and had been seeing each other on and off for several years, Clark said. Both were also in relationships with other people.
"So obviously that's where our investigation is going to start, because somebody knew that they were in the park at that time and obviously had an issue with that," he said.
Clark said nothing was taken and the case was not a robbery.
"You've got nine shots fired, all of them head shots to both of the victims, so it appears to be very much a crime of passion," Clark said.
Investigators have talked to a woman and are trying to talk to a man, but don't consider him a person of interest at this point.