GLENWOOD SPRINGS, JULY 31

More than 100 people had to spend the night on a highway, including nearly 30 who took refuge in a tunnel, after rain over an area burned by a wildfire once again triggered mudslides in western Colorado, authorities said Friday.

The people were caught with their vehicles on Interstate 70 in Glenwood Canyon on Thursday night. Those in the tunnel were stuck for about nine hours until crews could carve out a path through the mud to reach them at about 6:30 a.m. Friday, Garfield County Sheriff's Office spokesman Walt Stowe said.

The tunnel serves as a 24-hour operations center for the Colorado Department of Transportation, so it is relatively well-lit and has telephones, Stowe said. No injuries were reported.

The transportation department has accounted for 108 people, including 29 in the tunnel, who were stuck on the highway overnight. Between 65 and 70 people remained stranded at a rest stop Friday afternoon as crews worked to punch a safe passage through the debris.

Mike Goolsby, a regional director for the transportation department, said the area was affected by about 10 slides, some 12 feet (4 meters) deep and up to 150 feet (46 meters) wide.

"I'm very grateful that no one was hurt. ... We've tried our hardest not to have people in the canyon when these flash flood warnings hit, but it was the best case scenario for all of us based on the outcome this morning," he said.

Glenwood Canyon has cliffs towering up to 2,000 feet (610 meters) above the Colorado River, making it prone to rockslides and mudslides. In recent weeks, rain over the area burned by a wildfire last summer has triggered frequent slides, resulting in closures of I-70, Colorado's main east-west highway. Those closures have mostly occurred before the storm moves in, to prevent people from being trapped.

On Thursday, the canyon had temporarily closed earlier in the day as one storm cell approached but had reopened by the time a second storm cell moved in, which led to the vehicles and their passengers getting trapped.

Transportation officials say the section of interstate is expected to be closed at least through the weekend because of the significant cleanup underway and because of heavy rain in the forecast. The National Weather Service has issued a flash flood watch for the area.