A couple have both been sentenced to two life terms in prison for murdering a man and a teen girl then dissolving their bodies in acid.
Tiffany Rae Pierce, 24, and Augustus Standingrock, 27, burst into the home where Jackson Wiles, 24, and Marilyn Pickett, 15, were staying.
Standingrock was said to have knifed Wiles to death, before Pierce stabbed and slashed the throat of Pickett.
They hacked their victims' bodies to pieces, before trying to dissolve them into a vat of acid to dispose their corpses, reported KGVO.
A neighbour who heard Wiles and Pickett's screaming, alerted the police and when officers arrived they found the victims' partially dissolved remains in a basement.
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Pierce and Standingrock believed Wiles had sexually abused a young girl they knew and therefore said to have carried the attack.
The crimes were among the most shocking and gruesome ever committed in Missoula, western Montana.
Standingrock said in the court: "I apologise, there's nothing I can say or do to bring anything back."
Pierce, who was charged for brutally stabbed her female victim eight times, weeped in the court and apologised to the victims.
She said: "I would like to offer my deepest and most sincere apologies and condolences.
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"I would also like to apologise to my family and friends, not only for the shame and embarrassment and shock that I have caused, but also for the burden that I have become.
"It was never my intention to cause anyone's death."
Pierce pleaded guilty to two charges murder and attempted murder; Standingrock admitted murder and accountability for murder, according.
Both were given two life terms and sent to Montana State Prison.
