At least seven people have died after a dense “super fog” caused a huge, 158-car pile-up near New Orleans.

Thick fog and fumes from multiple marsh fires mingled to reduce visibility for drivers commuting on Monday.

Twenty-five people were injured in the crash on Interstate 55 in St John the Baptist Parish, said police, who warned the death toll could rise.

Some vehicles caught fire and were abandoned, leaving a trail of burnt-out wreckages and mangled metal.

Police said the motorway will remain closed until at least midday on Tuesday.

“A portion of the crash scene caught on fire shortly after the initial incident. One tanker truck carrying a hazardous liquid is being off-loaded due to a compromised tank/trailer,” Lt Melissa Matey said in a statement.

One car was driven off the road and into the water, but the driver was safely rescued, police told WWL-TV.

Mike Tregre, sheriff of St John the Baptist, said an estimated 100 people were stranded and school buses were being used to transport them to their destinations.

Clarencia Patterson Reed, 46, who was driving to Hammond, told local media she was able to avoid hitting the car in front of her, but the vehicles behind her began slamming into her car.

“It was ‘Boom. Boom.’ All you kept hearing was crashing for at least 30 minutes,” she said.

She was able to get out of her car, but her wife was trapped inside and was injured.

The National Weather Service in New Orleans described the weather phenomenon as a “super fog”, cautioning that similarly dangerous weather conditions could appear later this week.

On its website, it states super fog can form when a mixture of smoke and moisture from damp, smouldering vegetation mixes with cooler air.