MCCAMMON — Multiple local fire departments responded to a motorhome fire that shut down an Interstate 15 off-ramp in McCammon on Sunday afternoon.

The motorhome caught fire around noon on the McCammon exit's northbound off-ramp, according to the Bannock County Sheriff's Office.

The motorhome's occupants escaped the burning vehicle uninjured after coming to a stop on the off-ramp, authorities said.

The Inkom, Arimo and McCammon fire departments all responded to the blaze, extinguishing the fire before it could spread to nearby brush. The motorhome was destroyed and a car it was towing also suffered damage.

The northbound off-ramp was shut down for more than an hour because of the fire, though Interstate 15 itself remained open.

Authorities have not commented on what caused the motorhome to ignite, but a witness said one of its tires blew out and caught fire. The witness said the flames quickly spread to the rest of the motorhome and caused its propane tanks to explode.

Emergency units, including Bannock County sheriff's deputies and Idaho State Police, remained on the scene until around 5 p.m. Sunday.

The incident remains under investigation.