OAKLAND, Calif. - A main road into Yosemite National Park reopened on Tuesday, and evacuation orders for nearby campgrounds and homes were lifted as fire crews gained ground against a blaze near the park.

The fire has scorched more than 5,000 acres since it erupted last Thursday, apparently sparked by a gas explosion in a motor home, but crews have now carved containment lines around half its perimeter, said Jim Tucker, a spokesman for the fire management team.

State Route 140 at the west entrance to the park was reopened to traffic at about 6 a.m. local time, and all campgrounds that had been shut down along the Merced River in adjacent national forests were reopened, he said.

Residents ordered evacuated on Saturday from the nearby village of Rancheria were also allowed to return home.

Part of Bridalveil Creek Campground inside Yosemite remained closed to the public for use as a staging area for firefighters, though plans call for releasing about half of the current force of 1,200 later in the day, Tucker said.

"We're asking people to use extreme caution because there are still fire personnel and equipment on the road," he added.

The fire caused five minor injuries, but no structures have burned.

The so-called Motor Fire is one of several California blazes in the past week that have heated up what had been a relatively calm fire season, marked by cool, damp weather, said Daniel Berlant, a spokesman for the California Department of Forestry and Fire Protection.

Cool weather prevents vegetation from drying and tends to keep moisture in the air. But abundant rains also spurred heavier growth in underbrush, building up fuel. As winds picked up, the fire hazard was now increasing, he said.

(Writing by Steve Gorman; Editing by Cynthia Johnston)

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