While the investigation into an explosion that burned seven teenagers on Monday night is ongoing, investigators said it appears a 55-gallon drum placed on top of a bonfire is to blame.
Clark County Public Information Officer Dan Kulin on Thursday said Clark County Fire Department investigators have interviewed witnesses and studied the scene.
A preliminary investigation shows about a dozen current and former Basic High School students gathered at an abandoned building in a desert area about five miles south of Horizon Ridge Parkway and Ray Boulevard in Henderson.
The teens used a flammable liquid to help ignite a bonfire near the structure, and at some point someone placed the drum on top of the fire.
At about 11:40 p.m., the heat from the fire increased the pressure inside the drum to the point where it ruptured, spreading the bonfire.
Seven burn victims were taken to St. Rose de Lima Hospital. Five of those victims were later transported to University Medical Center.
As of Thursday afternoon, three victims remain at UMC, one in serious and two in critical condition.
Clark County fire said you should never add unknown liquids or containers to a fire and that an apparently empty container may still hold volatile vapors that can ignite or explode.
Outdoor, unpermitted bonfires are illegal in unincorporated Clark County.
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