Los Angeles police began searching a California landfill Monday for evidence connected to the disappearance of Heidi Planck, a mother who is believed to have been killed in October after she attended her son's football game.
Police said in a statement that they were looking in "a specific area" of the landfill for human remains. Police said there is still no lead on a suspect in what they believe is a robbery-homicide case.
"Dateline NBC" reported that Planck's mysterious disappearance had investigators searching for clues in downtown Los Angeles, where her dog was found Oct. 17 — three hours after Planck, 39, was last seen — wandering on the 28th floor of a well-secured luxury building.
Planck's ex-husband, Jim Wayne, said he doesn't know how the dog got into the building and doesn't believe Planck knew anyone in the building, NBC Los Angeles reported.
"Forensic evidence was located inside the building which has led detectives to believe an incident occurred resulting in Planck’s death," police said.
Planck was first reported missing Oct. 20, and the case was transferred to robbery-homicide investigators Oct. 29. Planck's vehicle was found abandoned in a nearby parking garage Nov. 4.
Police said the investigation led them to the Chiquita Canyon Landfill, about 40 miles northwest of the downtown location where Planck was last seen.
Police said the excavation operation is expected to take over a week and warned of a potential "impact on community members who live around the Chiquita Canyon Landfill, specifically the community of Val Verde."
"Efforts are being made to minimize and mitigate that impact. We ask for the community’s understanding and support during this search and recovery effort."
Police asked for tips from anyone who was at the residential building at 1201 S. Hope St., listed online as the Level Downtown Flower building, on or around Oct. 17.
"Dateline" reported that Wayne said Planck left their son's football game at halftime that day behaving "edgy."
“She was a little bit antsy, yes. I don’t know why,” he said. “All I know is that was the last time I saw her or talked to her.”
Wayne filed a missing persons report shortly after Planck failed to pick their son up from school on Oct. 20.
"She’s a devoted mother who would never, ever leave her son," Wayne told "Dateline." "We have a 10-year-old boy at home that’s looking for his mom, and we just need to find her."
Video obtained by NBC Los Angeles and broadcast on Nov. 12 showed Planck walking downtown on Oct. 17 with her dog on a leash, hours after she had previously last been seen on security video leaving her home in west Los Angeles.