The fiance of a missing Colorado mother who vanished on Thanksgiving was spotted dumping trash at a waste facility with two other men after police searched his ranch for the first time.

Patrick Frazee, whose fiancée Kelsey Berreth vanished on November 22 after dropping off their daughter with him, was seen at the plant in Divide on Monday after police had left his ranch.

Employees at the ranch said Frazee was driving a white pick-up truck which was towing a trailer.

He did not get out of the vehicle but the two other men did to unload trash from the trailer. The two other men drove in two separate cars.

It is not clear if they arrived at the same time as Frazee or not.

Staff called police after recognizing Frazee and officers arrived to watch him through binoculars.

Patrick Frazee was seen at this waste facility on Monday in Florissant, Colorado, after police had searched his ranch. He was seen in a pick-up truck towing a trailer which two other men emptied. Police were called and later searched his home again but he is still not a suspect in his fiance's disappearance

Frazee's fiance Kelsey Berreth, left, has been missing since Thanksgiving and he is the last person to have seen her alive

They returned to his ranch on Tuesday afterwards to carry out their second search and they also retrieved bags of trash from the waste facility.

The Woodland Park Police Department is still however refusing to name Frazee as a suspect. The FBI, which is also involved in the search for Kelsey, has said nothing about the investigation.

On Tuesday, Woodland Park police officers said their return to Frazee's ranch was a 'routine follow up' search.

The Department is now offering a $25,000 reward to anyone who has information which could lead to Kelsey's whereabouts.

According to KRDO, the employees at the plant called them and the police after he arrived.

According to workers at the waste facility, Frazee stayed in his pick-up truck while two other men emptied trash from a trailer attached to it

Multiple police cars were seen at the plant but police would not confirm why they were there.

Frazee's attorney has insisted that he is cooperating with police and that he has nothing to hide.

He still has custody of their young daughter but has repeatedly refused to speak to media.

He says he was the last person to see her alive on November 22 when she dropped off their daughter with him.

Kelsey was last seen on surveillance cameras that morning grocery shopping with the pair's daughter.

Police searched his ranch on Monday (above) but returned after seeing him at the waste facility and searched it a second time on Tuesday

Frazee still has the couple's daughter in his care. They are shown last week as he refused to answer journalists' questions

It was not until November 25 that her concerned mother told police to say she had not heard from her.

She was officially reported missing on December 2.

Despite being engaged and sharing a daughter, Kelsey and Frazee do not live together.

Very little is known about their relationship. Her mother has spoken out only to plead for information which could lead to her return and the authorities are being extraordinarily tight lipped about her disappearance.

They revealed that when they searched her home, there were cinnamon rolls left out on the counter which had recently been baked.

Her cell phone pinged on November 25 in Idaho, hundreds of miles from her home.

On the same day, Frazee and her colleagues at a flight instruction school say they received text messages that she was not going to be at work for the following week.

Friends have described Frazee as a 'kind, old-fashioned cowboy' who would 'never' hurt her.

Police first searched his 35-acre property on Friday after the FBI became involved.