Homes burned as a fast-moving wildfire forced an entire Southern California mountain town to evacuate\u00a0Wednesday, while tourists emptied from the heart of Yosemite National Park so firefighters could battle a growing blaze nearby. Authorities ordered residents to leave Idyllwild, home to about 12,000 people, and surrounding forest communities in the San Jacinto Mountains east of Los Angeles. At least four homes burned as crews used aircraft to attack the flames that quickly burned nearly 2 square miles (5 square kilometers) of dry brush and timber in inaccessible terrain. No injuries were reported. Officers detained a motorist for questioning after people called 911 to report a suspicious vehicle near the fire's starting point in Riverside County, the California Highway Patrol said. The fire is one of several across California amid a statewide heat wave. To the north, in the San Francisco Bay Area, at least one home burned in a fast-moving wildfire in Clayton, where houses are spread out around windy roads. Yosemite Valley, the scenic heart of the national park, was closed at\u00a0noon\u00a0Wednesday\u00a0during the height of tourist season as smoke cast a pall on the region from a fire in the Sierra Nevada. The closure was heartbreaking for travelers, many of whom mapped out their trips months in advance to hike and climb amid the spectacular views of cascading waterfalls and sheer rock faces. ``We had one guest who planned a weeklong trip,'' said Tom Lambert, who owns a vacation rental property near Yosemite Valley. ``It was a father-daughter trip, for her high school graduation . Now it's done. It's sad.'' Another guest had to delay plans to climb Half Dome. The closure has also been a financial blow to Lambert and other businesses that rely on the summer tourist traffic. Most people left the valley\u00a0Tuesday, when officials reluctantly announced the closure, park spokesman Scott Gediman said. The remaining campers packed up their gear\u00a0Wednesday, joining the exodus that has been mostly orderly. ``People have been very understanding,'' Gediman said. Officials emphasized that Yosemite wasn't in imminent danger from the fire. Authorities decided on the shutdown to allow crews to perform protective measures such as burning away brush along roadways without having to deal with traffic in the park that welcomes 4 million visitors annually. On Wednesday, an extended family from Los Angeles on their annual trip to Yosemite prepared to leave the Upper Pines campground. ``Very disappointed,'' Lisa Salgado said. ``We look forward to this all year. This is the trip of our summer.'' The group arrived\u00a0Monday\u00a0and had planned to stay through\u00a0Saturday. Instead, they packed tents and other gear into vehicles, hoping they could find another campground elsewhere. ``So, this is a new memory,'' said Miguel Martinez. ``I've never been evacuated before.'' Yosemite Valley will be closed until at least\u00a0Sunday, along with a winding, mountainous, 20-mile (32-kilometer) stretch of California's State Route 41 that leads into the area, Gediman said. At least 1,000 campground and hotel bookings were canceled _ to say nothing of the impact on day visitors, park workers and small businesses along the highway, Gediman said. Rangers went to campsites one at a time to inform visitors of the closures. Hotels guests got phone calls and notes on their doors. ``This is the prime visitor season, so this wasn't an easy decision to make,'' Gediman said. ``This was purely for safety's sake.'' The last time the 7.5-mile-long (12-kilometer-long) valley was closed because of fire was 1990, he said. Lambert and his wife, Theresa Ho, were briefly evacuated last week when smoke cast an unhealthy pall over the home where they live upstairs and rent the downstairs to tourists.\u00a0 ``Basically June, July and August are the big revenue months,'' he said, estimating that about 100 nearby vacation properties would be forced to offer refunds.\u00a0 ``We're gonna lose half of July and half of August probably.'' Yosemite Valley is the centerpiece of the visitor experience, offering views of landmarks such as Half Dome, Bridal Veil Fall, El Capitan and Yosemite Falls. The glacial valley has been enveloped by a choking haze of smoke from the Ferguson Fire. Over nearly two weeks, flames have churned through 60 square miles (155 square kilometers) of timber in steep terrain of the Sierra Nevada just west of the park. The fire was just 25 percent contained. Mandatory evacuations are in place in several communities while other people have been told to get ready to leave if necessary. More than 3,300 firefighters are working the fire, aided by 16 helicopters. One firefighter was killed July 14, and six others have been injured. Rhonda Salisbury, CEO of Visit Yosemite\/Madera County, said the regional visitors bureau has been relocating tourists statewide following the closure. ``People are heartbroken,'' she said. ``Some want to ride it out for a few days and see if they can get back in the park.'' Others want help finding places to stay away from Yosemite. Gediman suggested valley visitors divert to Tuolumne Meadows, on Yosemite's northern edge, or to Sequoia and Kings Canyon National Parks to the south. ``There are wonderful places to visit in the region, so we're asking people to consider alternative plans,'' he said. In the state's far north, a 7-square-mile (18-square-kilometer) wildfire has forced the evacuation of French Gulch, a small Shasta County community that dates to the Gold Rush.