A 15-year-old girl was found mysteriously dead in Los Angeles early Monday morning -- and a motive and suspect in the case remain unknown.
The body of Samantha Bustos was found in Compton at about 1:30 a.m. local time, the Los Angeles County Sheriff's Department said.
Bustos suffered a "traumatic injury to her upper torso," the sheriff's office said.
The coroner's office ruled it a homicide but the sheriff's office did not release the teen's cause of death.
The teen's grieving family and friends gathered Monday where her body was found.
Victor Lopez, a cousin of the teenager, told ABC Los Angeles station KABC-TV. that Bustos was last seen Friday when she and her best friend went to a party -- and that Bustos was last seen with a few unknown males.
On Saturday, Bustos' friend asked Lopez if the 15-year-old came home, Lopez told KABC-TV.
"We couldn't find her and we started looking for her Saturday morning," Lopez said.
(MORE: Grisly details released in Boston mom kidnapping case: Her body was found bruised, bound, naked in suspect's trunk)Bustos' family reported her missing at the Compton sheriff’s station on Sunday, according to authorities.
"I was always overprotective over her," Lopez told ABC News via email Tuesday.
"Samantha was a great kid" and "a great student," he wrote. "Always goofy .. always a joyful person."
The sheriff's office said Monday night that a motive and potential suspect was unknown.
Anyone with information is urged to call the Los Angeles County Sheriff's Department's Homicide Bureau at (323) 890-5500.