That created a column of fire which then detached itself to form a floating, quivering fireball.

ECONOMIST: Ball lightning

"Forty-one survivors said that they smelled oil, but there were no witnesses of flames, fire or a water column, nor were there any injuries from these factors, " Yonhap quotes the full report as saying.

CNN: STORY HIGHLIGHTS

It isn't clear what caused the fire, but Arturo Montiel, a spokesman for the highway patrol, said the fire was concentrated in the rear of the car, and not in the engine column.

WSJ: Limo Fire on Bridge Kills Five