Investigators trying to find a Colorado mom who has been missing since Thanksgiving are searching her fiancé's home, police said Friday.

The Woodland Park Police Department said in a statement that they were in the midst of carrying out a search warrant with other agencies. Patrick Frazee's lawyer confirmed the search was being conducted at the fiancé's house.

"This case is the number one priority for the Woodland Park Police Department and we are working around the clock on it," the department said in the statement.

Woodland Park police chief Miles De Young told reporters Friday that detectives don't believe the missing woman, Kelsey Berreth, is hiding from loves ones and those searching for her.

"Our investigators believe that Kelsey's disappearance is more suspicious and that she is not intentionally avoiding efforts to find her," De Young said.

Frazee had already handed his phone, DNA and photos over to police and has been cooperating with investigators since his fiancée Berreth was reported missing by her mother on Dec. 2, his lawyer, Jeremy Loew, said in a statement Wednesday.

Kelsey Berreth was reported missing by her mother in Woodland Park, Colorado, on Dec. 2. Woodland Park Police Department

"Mr. Frazee was never asked to voluntarily participate in this search," Loew said Friday. "We encourage law enforcement to take whatever steps it deems necessary to find Kelsey Berreth and to be able to exclude Patrick Frazee as a possible suspect in this missing person investigation."

But De Young said the Frazee has not consented to a formal interview with detectives.

“We have yet to have him sit down with one or investigators and that’s what we’re asking for, just for him to sit down with an investigator since he was the last person to talk with Kelsey face-to-face from what we can tell,” De Young said.

Asked if Frazee has declined a formal police interview, the chief said: “He is communicating with us through his attorney and that’s about all I can say about that.”

Berreth, 29, was last seen in public on Nov. 22 at a Safeway grocery store in her hometown of Woodland Park. In footage posted on the Woodland Park Police Department's Facebook page Tuesday, Berreth is seen walking into the store with her daughter in a baby carrier.

Frazee, who doesn't live with Berreth and their 1-year-old daughter, told police he last saw his fiancée on Thanksgiving when he got his daughter, Woodland Park Police Chief Miles De Young said Monday. He said he last communicated with her on Nov. 25 when she sent him a text message.

Doss Aviation, where Berreth works as a flight instructor, also said they received a text message from her on Nov. 25, De Young said. In the message, she was asking for time off.

On that same day, Berreth's phone pinged to a location near Gooding, Idaho, about 800 miles away from Woodland Park, police said.

Berreth's mother, Cheryl Berreth, who lives in Idaho, said on NBC's Today that her daughter never mentioned any travel plans. She said when the two talked on the phone on Thanksgiving they discussed a recipe and Christmas.

"I can’t think of anywhere she’s ever gone where she hasn’t told me," Cheryl Berreth said. "It’s just not in her character to do something, to just take off and be gone."