Crews were making progress Thursday toward containing a wildfire that has burned four mountaintop cabins and was threatening hundreds of other houses near Casper.

The fire about five miles south of Casper was 30 percent contained, said Vince Mazzier, spokesman for the federal management team that's directing the firefighting efforts. The fire made several runs overnight and pushed its size to well over 10,000 acres — more than 15 square miles.

"In total, I think we're making good progress on the fire," Mazzier said. "If the weather holds today, I think we'll be getting quite a bit more progress. It's all weather dependent right now, and being able to get resources in to do the work."

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About 350 firefighters were on the scene, Mazzier said. People in hundreds of homes on Casper Mountain and surrounding areas have been told to evacuate since the lightning-sparked fire was reported Monday.

The fire had burned four cabins and was within a half-mile of many other houses, Mazzier said. There were no reports of injuries.

"We have lots of displaced people," Mazzier said. "And of course, they're always concerned about what's going on with their homes."

As the fire threatened her home, Heather Carter packed up a tea cup from her great uncle, her chef's knife, a cookbook and a "lot of shoes."

She then realized she was missing something else: her dog, Zoe, had recently died and her ashes were still unpacked.

"I didn't want her to burn twice," Carter told the Casper Star-Tribune.

Dennis Polk packed up his house alone; his wife and daughter were out of town. He told the newspaper he grabbed photographs and important documents before heading to a hotel.

"Tomorrow is another day," he said. "We're just wondering when we will be able to get back to go home or if there will actually be a something to go home to."