CRIPPLE CREEK, Colo. – A Colorado rancher was sentenced to life in prison without parole Monday shortly after a jury convicted him of beating his fiancée to death with a baseball bat and setting the woman’s remains on fire to hide the evidence.

Patrick Frazee was convicted of first-degree murder and other charges after the jury deliberated four hours. Less than an hour later, a judge sentenced him to the life term, plus 156 years, the mandatory sentence after prosecutors previously decided not to seek the death penalty.

"Your actions were vicious, senseless, without reason or explanation," Judge Scott Sells told Frazee.

Prosecutors said Frazee, 33, killed Kelsey Berreth, a 29-year-old flight instructor and the mother of their 1-year-old, in her home. She was last seen with her infant daughter on a grocery store video on Thanksgiving Day 2018. Her body was never found.

Frazee showed no reaction to the verdict, while Berreth’s family sobbed and hugged one another.

With little physical evidence, prosecutors relied heavily on the testimony of Krystal Lee, a former nurse who has known Frazee for over a decade, and the location of Frazee’s and Berreth’s cellphones in the days after she disappeared.

Lee, who lives in Hansen, Idaho, testified that Frazee asked her to clean up the scene of the killing and that she watched him burn a plastic tote she believed contained Berreth’s body.

Lee acknowledged she took Berreth’s cellphone with her to Idaho at Frazee’s request to try to deceive investigators about Berreth’s whereabouts. She reached a plea deal with prosecutors for tampering with evidence and faces up to three years in prison.

Frazee’s lawyers used the plea deal to question how honest Lee was about what happened since she initially told authorities she did not know who Berreth was.

Lee said Frazee tried to persuade her to kill Berreth several times before he called to tell her that he had a mess at Berreth’s home and he needed her to drive to Colorado to clean it up.

According to her account, Frazee covered Berreth’s eyes with a sweater and asked her to smell some candles before he started beating her while the couple’s 1-year-old daughter was in a storage room. Lee testified that Frazee said Berreth’s last words were, “Please stop.”

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Cheryl Berreth, Kelsey’s mother, said in a letter to the court that Frazee tortured her daughter to death and left her young granddaughter to “call out for mama in the middle of the night.”

“He not only killed our daughter – his child’s mother – but he chose a horrible death for her,” she said.

A partial human tooth was found on Frazee’s property where Lee says the bag was burned, but it did not have enough DNA to determine whom it belonged to. An expert testified that the burned plastic residue found next to a spot of oily dirt was consistent with a body being burned but acknowledged that motor oil could have left a similar stain.

Frazee’s lawyer, Adam Steigerwald, said no DNA evidence tied to Lee was found at Berreth’s home. Colorado Bureau of Investigation analyst Caitlin Rogers said that did not surprise her because the bleach that Lee said she used to clean up destroys DNA.

Lee showed investigators some small blood spots she said she purposefully left behind. Blood stains were also found between the slats of the home’s wood floor.

On the final day of testimony, jail inmate Jacob Bentley told the jury that Frazee asked him to kill Lee, her relatives and the case’s lead investigator while the two of them were housed near each other.

Prosecutors have not given a motive for the slaying. Berreth’s parents argue in a wrongful-death lawsuit that they believe Frazee wanted full custody of the couple’s daughter, who now lives with them.

Berreth was last seen at a supermarket with her daughter on Thanksgiving Day. Between then and Nov. 25, texts were sent between Berreth’s and Frazee’s phones about exchanging their daughter and Berreth purportedly wanting to break up.

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The phones were in the same location when those texts were sent, prosecutors said. After Nov. 25, Berreth’s phone started sending signals from Idaho.

Lee testified that she sent the last message from Berreth’s phone to Frazee – “Do you even love me?” – after returning to Idaho.

Witnesses testified that Frazee accused Berreth of abusing their daughter. Investigators said there was no evidence of any abuse.

A man who said he considered Frazee to be like a stepson, Joseph Moore, testified that when he asked Frazee how Berreth was doing in April 2018, he told him that he had figured out a way to kill her and get away with it.

Moore said Frazee was puzzled after Berreth’s disappearance garnered national attention.

“He’s like, ‘Man, if I had known it was going to blow up this big, I never would have ...’ And he stopped. He did not finish that sentence.”