So he was found in the landfill where they have been searching.

https://www.kare11.com/article/news/...b-0db47132a33e


Anoka County Sheriff Brad Wise said human remains were found in the Elk River Landfill, where authorities have been combing through waste since early June.

"I assure you, it’s a sobering experience to work in a landfill like that, only to discover someone else’s child," Wise said.

"We were offered information that led to a video, and that video showed that the body might have made its way into a dumpster and then a landfill," Wise said.

According to Wise, the remains were found Saturday afternoon, and by Monday, DNA results had verified the remains belonged to Collins.
Collins' father was the last known person to have contact with the teen, but Wise stopped short of calling him a person of interest in the case. He said authorities remain in contact with him as the investigation continues. However, Wise confirmed police do have at least one person of interest, and they're treating Collins' death as a homicide investigation.