Emergency crews are searching for three people reported to be missing after a massive mudslide struck in western Colorado's Mesa County, CBS News reported.
About 40 miles east of Grand Junction, the slide hit Sunday in a remote area near the town of Collbran.
The mudslide followed a day of rain and is located about 11 miles southeast of the town of Collbran, a community of about 700 people in western Colorado, CNN reported.
"This slide is unbelievably big," said Lt. Phil Stratton with the Mesa County Sheriff's Office late Sunday. It's estimated to be about 4 miles long, 2 miles wide and about 250 feet deep.
After the incident was reported around 6 p.m., rescuers raced to the scene but eased operations after nightfall since the zone is unstable, Mesa County Sheriff's spokeswoman Lisa McCammon said.
There's "not a lot of activity tonight," she said. The "slide area is very unstable."
A daylight search would prove to be much safer.
Three residents of the Collbran area who, the Denver Post cites the sheriff's office as saying, might have been swept away by the slide were being searched for by several crews, the department said.
The site is in a rural part of the county and there were no reports of any structures damaged or major roads affected, McCammon said.
There is no cell phone service in the area, the Denver Post reported.
The sheriff's office said that the person who reported the slide at about 6:15 p.m. "described hearing a noise that sounded much like a freight train."
"A unified incident command has been established between Plateau Valley Fire Department and the Mesa sheriff, to handle the slide and search for the people possibly caught in it," CBS News reported.
The avalanche occurred about two months after a massive mudslide hit the Washington state community of Oso on March 22, killing 43 people.
