David Webb-Kim on Unusual Suspects: Admits to 'Most Heinous Crime,' 1991 Murder and Rape of 9-year-old Amanda Gaeke [VIDEO]

ID channel's latest episode of "Unusual Suspects" studied the 1991 case of 9-year-old Amanda Gaeke, a young San Diego girl who was raped and murdered by her then-16-year-old neighbor, David Webb-Kim. The crime, deemed "the most heinous crime ever seen in the county" at the time, went unsolved for five years - until Webb-Kim was questioned by police and finally admitted to the morbid abduction, rape, and murder. Investigators look back on "Unusual Suspects" and remember Webb-Kim as a teenage sociopath who seemed to have no remorse about his treacherous actions.

The body of Gaeke was found decomposed in North Park Canyon in October, 1991 - she had been missing for 11 days prior. It wasn't until years later that San Diego police received a tip leading them to Webb-Kim. When questioned, the young man openly confessed to abducting Gaeke as she rode her bike past his house on October 3, 1991. Unbeknownst to Webb-Kim's parents, he kept Gaeke locked up in his bedroom before ultimately killing her. He admitted to authorities that he "drugged, tortured, and raped her for two days before ultimately killing her and dumping her body in the woods."

An investigator interviewed for the recent "Unusual Suspects" episode remembers Webb-Kim's chilling demeanor - "He never really showed any remorse about what he'd done. He never broke down. He was very matter-of-fact about the whole thing." Other witnesses referred to him as "a monster at 16-years-old" and a teenage "sociopath."

Catch a clip of ID's "Unusual Suspects" which delves into the case of Webb-Kim and Gaeke here:

Webb-Kim plead guilty to all of the charges filed against him and is currently serving a life sentence in prison.

"Unusual Suspects," an investigative series narrated by Mocean Melvin, airs on ID on Sundays at 10 p.m. E.T.