'Doomsday' couple Lori Vallow and Chad Daybell charged with murder

Lori Vallow and Chad Daybell, a US couple at the centre of a bizarre and long-running criminal investigation, have been charged with murder.

Both face first-degree murder charges for the death of Vallow's children from two previous marriages - Joshua "JJ" Vallow, seven, and Tylee Ryan, 17.

The bodies of the children were found at Mr Daybell's home last year.

The case has gained widespread media attention because of the couple's links to "Doomsday" apocalyptic beliefs.

Chad Daybell is an author who has written several apocalyptic novels loosely based on Mormon religious teachings. The couple are thought to have met through their involvement in a movement that promoted preparing for the end of the world.

Mr Daybell has also been charged with the murder of his ex-wife, Tammy Daybell, who died suddenly just weeks before he married Vallow.

Both have been in custody since last year and were previously accused of concealing evidence but Tuesday marks the first murder charges against them.

The couple also face conspiracy and other charges, including theft and insurance fraud.

"We have cause to believe that the Daybells wilfully and knowingly conspired to commit murder of three innocent people," Fremont County Prosecutor Lindsey Blake said.

The couple will appear in court later on Wednesday.

New charges were announced against the couple on Tuesday, almost a year after the two children's bodies were discovered at an Idaho property belonging to Mr Daybell.

Prosecutors say the two children were last seen on different dates in September 2019. They were reported missing by their grandparents in November, when police discovered they had not been seen for weeks.

Authorities previously said their mother had provided misleading answers to investigators' questions and outright lied about their whereabouts before allegedly fleeing the state.

Lori Vallow, who also goes by Lori Daybell, was eventually arrested in Hawaii in February for child abandonment and contempt of court after missing a January deadline to deliver her children to authorities.

Mr Daybell was then arrested in Idaho after the children's bodies were discovered months later at a property he owned.

Court documents revealed that Tylee's body was found dismembered and burned and JJ's body was wrapped in tight black plastic and tape.

Tylee was born during Lori Vallow's third marriage to a man named Joseph Ryan. She and her fourth husband, Charles Vallow, adopted JJ from a family member.

The murder charges were announced on what would have been JJ's ninth birthday.

Announcing the charges on Tuesday, investigators said "thousands of hours" had been spent by officials "seeking the truth for these innocent victims" and blamed the pandemic for the charge delay.

"I want to assure everyone that despite the delays, we have been working diligently to pursue justice for the victims in this case, to ensure we have the evidence required to prove the facts beyond a reasonable doubt in a court of law," Prosecutor Lindsey Blake said.

The case has been surrounded by speculation because of the couple's beliefs and links to a number of suspicious or unexplained deaths.

Friends say Lori had become a "superfan" of Mr Daybell's books and the couple appeared on a podcast together in December 2018, according to US media reports.

Lori later moved from Arizona to a town in Idaho where the author was based in late August 2019 after her then-husband, Charles Vallow, was shot dead by her brother, Alex Cox - who said the killing was self-defence.

Cox himself also died in December 2019, aged 51, of what a medical examiner determined to be natural causes.

Before Charles Vallow was killed by Cox, he had filed for divorce and raised concerns about his wife's beliefs, alleging she had "become infatuated, at times obsessive, about near-death experiences and spiritual visions".

Lori then married Chad Daybell in October, just two weeks after the death of his wife Tammy.

According to her obituary, Tammy Daybell died of natural causes, but police later ordered the exhumation of her body. An autopsy was finalised in February this year. Her family thanked law enforcement in a statement released on Tuesday.

No cause of death has been released for the victims but the criminal indictment said the couple justified their crimes using their religious beliefs.

The couple are scheduled to appear in court via Zoom on Wednesday but have previously denied all charges against them.