GOLDEN, Colo. - Teenager Austin Sigg pleaded not guilty in court Friday to the kidnapping and murder of 10-year-old Jessica Ridgeway. Jessica's father lives in Independence, Mo.
Austin Sigg entered the plea during a hearing that began at 1:30 p.m.
Last month, Sigg's attorneys brought up his mental health, indicating a plea of not guilty by reason of insanity was still on the table, but instead Sigg pleaded not guilty Friday.
During a preliminary hearing earlier this year, prosecutors played a 911 call where Sigg admitted to killing Ridgeway and to trying to kidnap the jogger.
"I murdered Jessica Ridgeway, I have proof that I did," Sigg is heard saying on the recording. "I'm giving myself up completely, there will be no resistance whatsoever."
When the dispatcher asked Sigg if he had a criminal history, he confessed to a second crime.
"The only other (incident) was Ketner Lake, where a woman was attacked. That was me," Sigg said.
-- We caution readers that this story below contains gruesome details.
Jessica was abducted as she walked to school on Oct. 5, triggering a massive search that ended with the discovery of her dismembered body five days later in an Arvada open space field.
Jessica's remains were found when two men collecting litter in that field came across a shiny black plastic bag, lead Westminster Police Detective. Luis Lopez said.
The supervisor and the men cut open the inner bag and found the girl's torso, which was missing her arms, legs and head, Lopez said. The rest of the girl's remains were found in the crawl space of Sigg's home, the detective said.
An autopsy showed Jessica died from asphyxiation due to strangulation or suffocation, Lopez said.
Sigg came onto investigators' radar on Oct. 19, when a neighbor woman called a tip line in response to police saying they had recovered a small wooden cross that might have been worn by the killer.
The neighbor said she knew a teen named Austin Sigg who had worn a similar cross, according to Lopez.
The woman said she was concerned about Sigg because he had dropped out of high school and "he was obsessed with death and the decomposition of bodies," the detective recalled.
Based on that tip, the FBI took a DNA sample from Sigg that day, Lopez said. That was four days before the 911 call where Sigg confessed to the dispatcher.
Lopez said Sigg's DNA was linked to "touch" DNA found on Jessica's torso, underwear, water bottle, boots and gloves as well as the clothing of the jogger who was grabbed at Ketner Lake.
During a search of Sigg's home, police seized computer equipment.
Westminster Police Detective Chris Pyler, who specializes in crimes against children, testified that child pornography images were recovered from a laptop and a computer tower seized at the home.
The Sigg family did not know the Ridgeway family, Lopez said. But it might have been a crime of opportunity.
In court, prosecutors presented a map showing the location of the jogger's attack, Ridgeway's home, and Sigg's home. All were within one mile of one another.
Sigg studied mortuary science at Arapahoe Community College and had interest in becoming a mortician.