A flash flood hit Boulder, Colo., early Thursday morning, killing at least one person, The Denver Post reported.

The National Weather Service declared a flash flood emergency through 4:15 a.m. after a long evening of rain caused area waterways to overflow. Four to six inches of rain has fallen on the area since mid-day Wednesday, the weather service said.

Almost all roads to Boulder have been cut off due to major flooding, prompting officials at the Boulder Office of Emergency Management to issue a warning, urging motorists to avoid driving through flooded areas.

The flooding has caused at least one fatality, the Boulder County Sheriff's dispatch confirmed. County officials told The Denver Post that multiple homes had collapsed in the Jamestown area.

As a precaution, the University of Colorado Boulder closed the campus on Thursday, and ordered hundreds of students, faculty and staff to evacuate.

More from The Associated Press

BOULDER, Colo. (AP) — Days of heavy rains caused flash flooding in Colorado's Boulder County early Thursday that has closed streets, prompted evacuations, and left one person dead.

The National Weather Service issued a flash flood emergency for the county and northwest Jefferson County, while a mandatory evacuation order was in effect for the tiny community of Jamestown and the Fourmile area.

The Weather Service said that county officials reported some homes had collapsed in Jamestown, where dozens of people live, according to a report by the The Denver Post.

Boulder Office of Emergency Management spokeswoman Gabrielle Boerkircher told The Associated Press that one person was killed when a structure collapsed in Jamestown, but that she didn't have any other details because the high waters have prevented rescuers from reaching the scene.

Meanwhile, about 400 students at the University of Colorado housing were evacuated and the campus was shutting down Thursday because of the flooding, Boekircher said.

In addition to the two counties where there were flood emergencies, the Weather Service posted flash flood warnings for parts of Broomfield, Adams, Weld, Larimer, and El Paso counties.

Mudslides and rockslides were reported in several areas, with parts of U.S. 6, Boulder Canyon, Colorado 14 and U.S. 287 all reporting problems and temporary blockages during the evening, the Denver Post said. Lefthand Canyon was reported blocked by one of the many slides.

Boulder police dispatchers were receiving calls of flooding basements and homes and of flooded streets and submerged cars.

Emergency Management Director Mike Chard said people should avoid creeks and waterways, and not attempt to cross flooded intersections in their cars.

As the flooding began Wednesday evening, the city of Erie was the hardest hit in the county with up to a foot of water across Erie Parkway, according to a report by KCNC.

As the rains continued, conditions deteriorated early Thursday across the region.

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