A massive mudslide in rural Colorado has covered miles of forest and left three people missing. The mudslide occurred early Sunday evening in Mesa County, Colorado.

According to the Mesa County Sheriff’s Department, deputies responded quickly to calls about the slide at around 6 pm on Sunday, establishing a joint emergency command with firemen, search and rescue teams, and road crews to deal with the disaster. One person who called in to report the incident described the sound of the mudslide as something similar to a freight train. A roadblock has been set up to isolate the area and authorities have asked the media to avoid getting too close.

Shortly after the mudslide, authorities received reports of three men missing in the area. As of this morning none of those three people have been located.

The size of the mudslide has made damage assessments difficult to ascertain. Poor cell phone reception in the remote area has also been a concern for rescue teams. Despite these hindrances, Mesa County authorities have stated that no structures were damaged by the mudslide and no major roadways were affected.

A helicopter flight was scheduled to fly over the area early this morning to provide images. An update on the situation from the Mesa County Sheriff’s Office is expected this afternoon.

“This slide is unbelievably big,” said Lt. Phil Stratton of the Mesa County Sheriff’s Office.

Authorities have estimated that the mudslide was four miles long and two miles wide. The Sheriff’s Office has also estimated that the slide could be as deep as 250 feet in “many places.” The ground in the area is still quite unstable and authorities believe the ground continued to shift for much of Sunday evening.

Though mudslides can be caused by many different factors, Mesa County authorities believe that heavy rains in the area may have been a major factor.

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