The 18-year-old accused of kidnapping and killing Jessica Ridgeway will stand trial for murder.

A detective testified at Austin Sigg's preliminary hearing Friday that Sigg kept some of the girl’s remains in a crawl space at a home he shared with his mother.

The teenager, Austin Sigg, had been on investigators’ radar before a neighbor called a tip line suggesting they check him out because he seemed preoccupied with death, Westminster police detective Luis Lopez said.

Two FBI agents responded and took a DNA sample from Sigg on Oct. 19, four days before his mother called to say he confessed to killing Ridgeway. Sigg’s mother also told authorities of the human remains.

Lopez said the remains were later identified as Jessica’s and that DNA samples link him to Jessica’s remains and clothing.

Friday a judge decided that there’s enough evidence for Sigg to stand trial on charges of murder, kidnapping, sexual assault and robbery in Jessica’s death.

Sigg will be arraigned on March 12th.

Jessica’s disappeared while walking to school on Oct. 5. Some of her remains were found in garbage bags in an open space park five days later. Friday was the first time investigators revealed that the bags contained her torso.

The case set parents in the Denver area on edge as weeks passed without an arrest. Hundreds of officers canvassed the area and investigated leads and took DNA samples as parents waited with their children at bus stops and thought twice about letting them out of sight.

Police asked residents to be on the lookout for anything suspicious from their bosses, friends and family members, watching for things like leaving home unexpectedly, missing appointments or changing their appearance.

Lopez said Sigg’s mother turned her son in on Oct. 23, a day before testing was completed on the DNA sample taken based on the neighbor’s tip.

Former classmates of Sigg described him as a smart and interested in mortuary science.

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