Deven is accused of murdering and abusing two of her adoptive children before trying to conceal their bodies.
Police say they're particularly looking for the burn pit they believe Deven last used at her home on Berridale Drive. Police accuse her of using it to incinerate body parts before trying to conceal them at another location--and police say finding it could lead to their next breakthrough.
"The start of this case, we were already on on the back foot," says the lead detective on the case, Sarah Shirey. "You know, we didn't know anything about these children or this family until the police department becomes involved. And by then, we were already five years behind the eight ball. So we're trying to play catch up and figure out who these people are, who they associate with. And that's been our hardest thing. They don't really associate with anybody. They don't really have the traditional friends, the church groups, you know, the sports teams, things like that."
The Fayetteville Police Department says Blake and London Deven --the two children they say were killed by their adoptive mother Avantae Deven - haven't been seen since 2017 and 2019, respectively. Plus, they say the Devens were intensely reclusive.
One thing police say they specifically want to know more about is the burn pit they say Deven used at her Berridale Drive home to allegedly incinerate body parts.
"With the Berridale Drive burn pit, we'd be able to get some trace evidence that would corroborate some of our testimonial evidence that we have."
Police are also drawing more awareness to these nine aliases they know she used over the years.
They're also releasing a new photo of Deven from the '90s when she was going by the names "Michelle Spiegel" and "Prentiss Adams."
"If they know her as, say, Kim Nelson, you know, and not as Avantae Deven, that would be huge for us. And just those interactions, did they ever see the kids with them? What did the kids look like? What was the status? You know, what were the homes like?"
The Fayetteville Police Department also says they've set up a new tip line just for this case. That number is 910-578-2697.
WATCH | Timeline in Blake and London Deven Case
Timeline in adopted kids disappearance case
Fayetteville Police continue to appeal to the public for information that could help them create a timeline in the investigation into Blake and London's death.