(CNN) - The fiancé of missing Colorado mother Kelsey Berreth killed her by wrapping a sweater around her head and bashing her with a baseball bat and later burned her body in a water trough, according to testimony at a preliminary hearing in Cripple Creek, west of Colorado Springs.
On Tuesday, nearly three months after Berreth went missing, prosecutors filed new charges against Patrick Frazee, including tampering with a body and counts related to a crime of violence. He was arrested in December on murder charges and is being held without bond.
Colorado Bureau of Investigations agent Gregg Slater then testified about his interview with Idaho nurse Krystal Lee Kenney, who told investigators she had an intimate relationship with the defendant in early 2018 and provided details of the Thanksgiving Day killing, including that the weapon was a baseball bat. Kenney pleaded guilty to evidence tampering on February 8.
Berreth, 29, vanished last Thanksgiving, November 22, near Woodland Park, a city between Denver and Colorado Springs. Her body has not been found.
The couple has a 1-year-old daughter, Kaylee, who is now in the custody of Berreth's parents. A judge scheduled an April 4 hearing to determine the next steps in Kaylee's custody case.
Frazee tried to enlist Kenney to dispose of the body in Idaho but she refused, according to Slater. Instead, he removed the body to a farm in Fremont County, where it was kept for a time in a black tote bag in a stack of hay while he went to Thanksgiving dinner, Slater testified.
Frazee later moved the body to a water trough and added gas and wood before setting it ablaze, Slater said, adding that Frazee scooped up the singed remains and disposed of them either at a dump or in a river.
Frazee wanted help with killing, testimony says
Kenney told investigators Frazee had asked her to help kill Berreth on three occasions but that she couldn't bring herself to do it, according to Slater. Frazee told Kenney he feared for the safety of his daughter because, he said, Berreth was abusive and used drugs.
The first attempt, in September 2018, was supposed to involve poisoned coffee, Slater said. Two other attempts the next month involved a pipe and a bat, Slater testified.
On November 22, Frazee called Kenney to say he needed her help cleaning up a mess in Colorado, according to Slater.
The next day, she drove overnight to Colorado, bringing with her latex gloves, a white cleaning suit, booties, bleach, two trash bags and a hairnet, according to the agent's testimony. She picked up a key at Frazee's home and opened the door at Berreth's townhouse to what she described a "horrific" scene, Slater testified. She spent hours cleaning, discarding blood-stained toys and other items.
"You don't know how hard it is to have Thanksgiving dinner after killing her," she recalled Frazee telling her, according to Slater.
In early December, investigators examining Berreth's bathroom found blood in the toilet, the bathtub exterior, the bottom of a trash can, the walls, floor, a towel rack, the vanity and an electrical outlet, according to Slater.
Slater, who assisted with the investigation into Berreth's disappearance, testified the blood matched a DNA profile created with samples taken from the Berreth family.
Berreth's brother, Clinton, had alerted investigators on December 4 to blood in her bathroom and evidence of attempts to clean it, Slater testified. Agents discovered the evidence in the bathroom two days later.
Slater also testified that Berreth's mother, Cheryl-Lee Ellen Berreth, told him she last spoke with her daughter on the morning of November 22. Berreth told Slater that her daughter said she had seen Frazee the night before and had gotten medicine for his stomach ailment before returning to her home. Berreth told her mother she planned to have Thanksgiving dinner with Frazee that night.
The first witness Tuesday was Frazee's mother, Sheila, who invoked her Fifth Amendment rights. Her attorney said she was refusing to testify and not cooperating with the investigation.
Another witness, Patrol Commander Chris Adams of the Woodland Park Police Department, played a recording of a November phone call with police in which Frazee said Berreth had called him to end their relationship. He told police she was not suicidal and that he returned personal items to her, including a handgun. He said he was going to "give her space."
Cell phone records produced at the hearing showed calls between Frazee and Berreth around the time of her disappearance. Cell phone towers indicated both phones appeared to be near her home or in the same location. There were also calls between Frazee and Kenney, who police say disposed of Berreth's phone.
Records tracked Kenney's phone to near Berreth's apartment, and surveillance video showed Kenney and Frazee together at a gas station near his home as he filled a 5-gallon gas can on November 24.
The mystery behind Berreth's disappearance
Berreth's parents, Cheryl-Lee and Darrell Lynn Berreth, believe a custody dispute was likely a "motive to kill Kelsey," according to a wrongful death lawsuit they filed.
"Upon information and belief, Frazee had motive to kill Kelsey in that he wanted full custody of [their daughter] KB and/or Kelsey to leave KB with him and Kelsey would not agree," said the amendment, filed in a US District Court on Friday.
According to a family member, Berreth met Frazee online two years ago when Berreth lived in Warden, Washington. Within months, Berreth moved to Colorado to be with Frazee, who has a business shoeing horses in Teller County.
Frazee told police he last saw his fiancée on November 22, when he picked up their daughter, making him the last known person to report seeing her alive.
Berreth's employer got a text from her phone on November 25, saying she wouldn't be able to work that week, police said. Frazee said she had sent a text to him that day, but the contents of that text haven't been released.
That same day, Berreth's phone was tracked to a location near Gooding, Idaho, according to Woodland Park police Chief Miles De Young. Gooding is roughly 800 miles northwest of Woodland Park.
Berreth's parents grew concerned after she didn't respond to calls or texts for a week. So Cheryl-Lee Berreth called Frazee on December 2 to ask about her daughter.
"Frazee responded with 'here's the story...' " and proceeded to make a series of "false statements, misrepresentations, and/or calculated omissions," a court filing states.
According to the lawsuit, Frazee told Cheryl-Lee Berreth that he and Kelsey broke up on Thanksgiving, and that "Kelsey agreed to share with Frazee 50/50 custody of their daughter."
Frazee faces two counts of first-degree murder and three counts of solicitation to commit murder in the first degree in addition to the charges added on Tuesday.
Prosecutors filed two murder charges because they have different theories. One is that he acted alone to kill Berreth; the other is that he -- either alone or with other people -- killed her during a robbery.
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