HILLSBOROUGH, N.C. — There are new developments in the mysterious death of a 15-year-old from Orange County.

In May, Cristen Carter, a popular Orange High School freshman, was found dead near the doorstep of her family's trailer at the Arbor Hill mobile home park.

At the time, all investigators could say was that her death was suspicious. There were no obvious signs of foul play and no gunshot or stab wounds.

A toxicology report by the state Medical Examiner's Office found Carter died from a cocaine overdose -- traces of cocaine were found in her body.

Now, a grand jury has returned a murder indictment. Lazaro Martinez, 24, is charged with killing Carter.

Investigators believe the trouble started at a motel in Durham. They claim Martinez and Carter were in a room with two others the night before she died.

A few days after Carter's death, Durham police charged Martinez with statutory rape, claiming he had sex with the underage girl.

Now, the Durham District Attorney's Office has charged him with Carter's murder, but will not discuss the case.

According to North Carolina law, a person can be charged with second-degree murder for taking part in a drug-induced death.

A second person is also charged in connection with the case. In May, one of Carter's friends, Erica Frazier, 19, was charged with contributing to the delinquency of a minor.

Investigators say Frazier drove Carter to the motel that night. Carter told her parents she was attending a tutoring session.