Kaine Horman, who was able to move back into the family's Portland home with the help of a judge's order, declined to say exactly why he believes a third party involved, but told The Oregonian in a statement that his opinion was "based upon briefings."
Terri Horman, the last person known to see 7-year-old Kryon alive, is living with her parents, 170 miles away from the home she once shared with the little boy, her husband and the couple's 20-month-old daughter. A judge ordered her out of the home over the weekend, just weeks after Kaine Horman fled with their little girl amid reports that Terri Horman allegedly approached the landscaper about killing him.
Kaine Horman also told The Oregonian that he changed the locks on the house's doors and fence.
Terri Horman has not been charged or named a person of interest in Kyron's disappearance or in the alleged murder-for-hire plot, but police and the second-grader's family are hoping the pressure she's now living with will cause her to crack.
"Catching criminals is a lot like catching fish," said criminal defense attorney John Hingson III, who is not involved with the Horman case. "What you need to do is to let the fish run and don't try to grab him before it's too early. The police are letting Terri Horman run."
Terri Horman and her attorney have declined to comment on the allegations made by Kyron's parents. Her lawyer, Stephen Houze, said that his client has been receiving death threats and that the media frenzy surrounding the case has morphed into a "witch hunt."
Bruce McCain, a retired captain with the Multnomah County Sheriff's Office, which is investigating Kryon's disappearance, said the case was at a crossroads and will remain that way until investigators can determine whether Kyron is dead or alive.
"Kyron is the absolute key," he told "Good Morning America." "Without Kyron's status known there probably won't be an arrest any time soon."
Kyron disappeared from his elementary school science fair on June 4. While Terri Horman was seen by her husband's side, presenting a united front with Kyron's biological mother and her husband, the family began to distance themselves from her within weeks.
Kyron's parents have publicly said they believe Terri Horman had something to do with the little boy's disappearance and his mother, Desiree Young, has pleaded with her more than once to tell police what she knows.
Kaine Horman, who was granted an emergency restraining order to keep his wife away from him and their daughter, filed for divorce last month, but it still wearing his wedding ring.
He told ABC's Portland affiliate KATU that even that decision was part of the plan to find Kyron.
"I think I keep it on as a symbol of our family and more for our kids than anything else," he told KATU. "It will come off at some point but right now the priority is getting Kyron home and taking care of Kiara."
McCain said Kaine Horman's public statements and accusations against his estranged wife are "very, very telling" with regards to what information the family and investigators have.
But until Terri Horman starts cooperating, it will be up to investigators to remain engaged in "cubicle warfare" -- tracking down every lead and continuing to keep the pressure on.
"Right now Teri Horman is doing a very good job remaining tight lipped," McCain said.
Court Documents Detail Affair, Alleged Abduction Attempt
Court documents released last week added to the growing list of odd behavior coming from Terri Horman. Her husband claimed in a filing in which he attempted to have his wife held in contempt for violating the emergency restraining order granted June 28 that she tried to "abduct" her 20-month-old daughter from a gym day care after the emergency restraining order was granted.
And while the rest of the family was consumed by the search for Kyron, Terri Horman was allegedly carrying on an affair with 37-year-old Michael Cook, a former classmate of Kaine Horman's, according to the documents. The affair purportedly began four days after Kaine Horman moved out and investigators, according to the court papers, said they've "obtained hundreds of text messages, as well as several photographs of respondent [Terri] in various stages of undress and graphic sexual activity."
The court documents accused Terri Horman of sharing sensitive information with her new boyfriend about the police investigation into Kyron's disappearance.
The new allegations came hours after Houze sent a letter to the judge stating that she would not contest the restraining order that would keep her away from her daughter, or her husband's request to move out of the family's Portland home.
Cook told a local television station that he was planning to hire an attorney, but while there was "inappropriate communication" with Terri Horman, he never had sex with her.
Kaine Horman, told "Good Morning America" earlier this month that Terri Horman seemed to change after the birth of their 19-month-old daughter, Kiara.
"She went through some post-partum depression after the birth and her emotional state was more erratic," Horman said.
In his application for the restraining order, Kaine Horman wrote,"I believe respondent is involved in the disappearance of my son Kyron who has been missing since June 4, 2010."
He added, "I also recently learned that respondent attempted to hire someone to murder me. The police have provided me with probable cause to believe the above two statements are true."
Young said she didn't believe Terri Horman from the beginning when she called to tell her that Kyron went missing from his elementary school.
"There was just certain details that just didn't make any sense that gave me that sick to my stomach feeling," Young said.
At a recent press conference, she implored Terri to tell the family where he is.
"Unfortunately I am kind of at that point where I am so angry I just don't even have words," she said. "I just really want her to do the right thing ... Kyron is still out there and he needs to be home."
Kaine Horman said he feels betrayed.
"I think we all do," Young added.