Twin Falls, Idaho police announced Saturday on the city's website that the FBI had reached out to their department and the Twin Falls County Sheriff's Office to ask for their help on Dec. 15.

Investigators with both departments worked with the FBI and the Colorado Bureau of Investigation to prepare and serve several search warrants and process some items of evidence in the case of missing 29-year-old Woodland Park mom Kelsey Berreth.

9NEWS has reached out for additional information.

In a joint statement, Sheriff Tom Carter and Chief Craig Kingsbury of Twin Falls, said: "We are pleased our organizations were able to provide the assistance and support requested by the FBI, CBI and the Woodland Park Police Department."

RELATED: Kelsey Berreth case: A timeline of events so far

Their announcement comes one day after Patrick Frazee, Berreth's fiancé, was taken into custody at his home in Florissant by members of the multi-jurisdictional team including the Teller County Sheriff’s Office, Woodland Park Police Department and the FBI.

Berreth was last seen in surveillance video shopping at a Safeway store with her 1-year-old daughter in Woodland Park on Nov. 22. Cheryl Berreth, Kelsey Berreth's mom, first reported her missing on Dec. 2 after she contacted Frazee and said she had a difficult time getting ahold of her, according to law enforcement.

Frazee was arrested and is expected to face charges of first-degree murder and solicitation for first-degree murder. No additional arrests have been made yet, but that is an "absolute possibility," according to Woodland Park Police Chief Miles De Young.

Frazee was advised of his charges Friday afternoon from the Teller County Jail. He's slated to appear in court again the morning of Dec. 31. 

Frazee has no prior criminal record in Colorado, according to Colorado Bureau of Investigation records. He is currently being held without bond. 

Frazee's arrest comes one week after police initially executed a search warrant at his 35-acre Florissant property, which is about 15 miles west of Woodland Park where Berreth was last spotted shopping at a Safeway store with her daughter on Nov. 22. 

The couple’s daughter, who had been with Frazee until Friday morning, has been taken into protective custody.

According to a court docket, Berreth had a temporary custody hearing scheduled for Dec. 27.

Berreth's phone pinged in Gooding, Idaho on Nov. 25. She has family in Idaho and Washington, according to a missing persons bulletin for the case.

The same day her phone pinged in Idaho, De Young said she sent a text to her employer and said she wouldn't be in the next week.

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