The woman whose body was found buried in a shallow grave near a house in Alabama died of an accidental drug overdose, NBC News reported Thursday.

A toxicology report for 29-year-old Paighton Houston had been pending since her body was discovered in the grave in Hueytown, near Birmingham, on Jan. 3.

Houston was last seen the night of Dec. 20, leaving the Tin Roof bar in Birmingham with two men she didn’t know, authorities said.

Convicted rapist Fredrick Hampton, 50, was arrested earlier this week in Ohio and charged with abuse of a corpse for disposing of her body in the grave.

Authorities said they have evidence Hampton was with Houston the night of Dec. 20, but stopped short of identifying him as one of the men she’d left the bar with.

He was initially taken into custody Dec. 28 but was released two days later because investigators said they didn’t have enough evidence to charge him with a crime.