Last month, police announced that they had arrested and kept two individuals in custody in connection with the abduction of Vaughan, who was last seen on July 27, 2021.

Sarah Wondra, 35, and her husband Stacey Wondra, who live minutes away from Vaughan’s Fruitland home, were accused of failing to notify authorities about a death and arrested. At the time, police said that further arrests are likely.

The Fruitland Police Department issued a press release on its Facebook page on Thursday detailing the latest developments.

“The Fruitland Police investigators believe that there are four individuals involved in the abduction of Michael Vaughan,” the press release read.

“Two of the individuals are in custody, Sarah and Stacey Wondra. The following two individuals are needed for questioning:

“Brandon Shurtliff, 30, of Kuna, Idaho. He is currently believed to be in North Dakota. Adrien Lucienne, 32, a male, of Toledo, Ohio. He is currently believed to be in Toledo, but floats between California and Ohio.

“We believe that both Shurtliff and Lucienne have first-hand knowledge of Michael’s abduction.”

The police encouraged both to contact them as the “window of time for talking is closing.”

The press release also detailed the information that led to the police arresting Wondras. They noted that despite searching the home of the couple, the remains of Vaughan have not been found.

The release said: “We received credible information that the remains of Michael Vaughan could be found in the backyard of 1102 Redwing Street in Fruitland [the home of the couple].

“The Fruitland Police Department obtained a search warrant for the residence along with the front and back yards. The search warrant was served on Nov. 11. Upon entry, officers encountered Sarah Wondra.

“She was subsequently arrested based on probable cause that she had knowledge of Michael’s death and failed to report the death to law enforcement.

“The following day, the Fruitland Police Department joined by the Idaho State Police, Idaho Mountain Search and Rescue, Fruitland Fire Department, and the Fruitland Public Works Department began a methodical excavation of the backyard of Wondra’s home.”

Police believe that Vaughan was initially abducted and is deceased, and that his remains were buried at the home but later moved from the property.

Lauren Matthias, the host of Hidden: A True Crime Podcast and a spokesperson for the Vaughan family, has previously spoken to the media about how the family is handling the situation.

Speaking about Vaughan’s mother, Brandi Neal, in mid-November, Matthias told News Nation: “[Brandi] is not doing OK. That is a direct quote from her. ‘We are not OK. I’ve had to tell his siblings that he might not be coming home.’

“When law enforcement went over…to kind of debrief them and let them know what was going on [at the time of the arrests of the Wondras], they specifically said to Brandi, ‘Do not come over to this house.’”

Referring to Neal’s reaction, Matthias told News Nation: “She said, ‘This is my baby, this is my baby.’ She said she was pacing back and forth trying so hard not to go over to that house. She did start crying when she said the words ‘remains’ were used.

“She said, ‘I’m not there yet. I’m not ready to use that word yet. There’s still hope. I’m not ready to tell his siblings that he’s not coming home, not yet.’”

Newsweek has contacted the Fruitland Police Department for comment.