A deadly combination of smoke and fog in Louisianna is to blame authorities say for a 168-car pileup that killed eight people and injured 68 others. The weather event affected both lanes of traffic and a fire broke out not long after the start of the accidents. Crews are still working to sort out exactly how bad the damage really is.

At this stage, it’s unclear how the very beginning of the crash occurred. During the early stages first responders transported 25 individuals to local hospitals and police say that an unknown amount of people sought medical care on their own. At some point, a tanker truck with hazardous liquid became part of the crash though it’s unclear if there was a spill.

Initially, the crash was so bad that it caused two other highways to shut down. At this point, those are reopened but there’s no timeline in place for when I-55 might open back up. According to the Louisianna State Police, crews finally removed all involved vehicles late Tuesday.

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Despite that, the damage assessment is still ongoing as there are concerns about the condition of the bridge itself. As of 5:00 p.m. central time, DOTD bridge inspectors were on site and conducting preliminary inspections. The bridge will not reopen until both the DOTD and the LSP agree that it’s safe.

Authorities say that super fog (yes, that’s the technical term) situations arise out of a combination of smoke, moisture from damp but smoldering organic material, and condensed water vapor. It’s rare but could happen again over the next few days or weeks in the area. That was the situation that drivers on Interstate 55 near New Orleans were facing on Monday according to ABC News.

Police indicated that drivers who might have left their vehicle in the crash can find it by contacting Troop B at TroopB@LA.gov. The DOTD also provided some tips for drivers who might encounter just such a super fog. They include turning on your low-beam headlights if you can’t see 500 feet ahead, reducing speed, and minimizing distractions behind the wheel.

Image Credit: ABC 7 Chicago