This is an archived article that was published on sltrib.com in 2016, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

A wildfire in northern Utah's Box Elder County had topped 10,000 acres Thursday, but crews were keeping flames away from two ranches as the blaze smoldered and flared in grass and rangelands near the Utah-Idaho border.

The Broad Mouth Fire, which was 15 percent contained, was first spotted about 11:30 a.m. Wednesday. More than 100 firefighters were fighting it, aided by water-laden aircraft and light winds blowing flames away from the few structures in the sparsely populated region.

Early on, however, the fire did destroy a cabin, a camp trailer and mobile home, all unoccupied, said Box Elder County Fire Marshal Corey Barton.

The fire began just west of Interstate 15 and north of Interstate 84, near the tiny town of Plymouth, some 15 miles south of the state line.

The cause of the fire reportedly was human-caused, but initial indications were it was accidentally set. No further details were released, as the cause remained under investigation.

The Interagency Fire Center reported that smoke from the fire drifted as far south as the Salt Lake Valley, contributing to a brownish haze over the Wasatch Front.

Twitter: @remims