USA: Seven killed in crash involving nearly 160 vehicles

Not less than seven people have died in an accident inferno in dense fog involving a total of 158 vehicles in the US state of Louisiana. At least another 25 people were injured, some of them seriously.

They were taken to hospitals after the pile-ups at west of New Orleans, the state police said.

"It was possible that more fatalities would be found. Part of the scene of the crash on Interstate 55 caught fire, partly because a tanker loaded with a dangerous liquid caught fire. Once the vehicle was recovered, the situation could be better assessed," the police added.

Photos released by the police show a debris field of cars destroyed and pushed into each other on both sides of the road. The stretch of highway runs between Lake Maurepas and Lake Pontchartrain. Meteorologists spoke of a "super fog" that severely impaired visibility between the communities of Ruddock and Manchac at the time of the pile-ups on Monday morning, according to CNN.

The "incredibly dense fog" was caused by a combination of fog and smoke from nearby fires, according to the National Weather Service.

The "super fog" is a particularly dense fog that develops in humid, smoky conditions and can cause visibility to drop to less than three metres, the National Weather Service said.