NEW ORLEANS (AP) — The death toll from last week’s series of highway crashes blamed on a “super fog” of smoke from marsh fires mixed with dense fog has been lowered from eight to seven people, according to Louisiana State Police.

The Oct. 24 pileups involved about 160 vehicles on Interstate 55 near New Orleans.

“Due to the intense fire and the extensive wreckage, the initial investigation led Troopers to believe that there were a total of eight victims,” state police said in a Friday news release.

The final number was lowered to seven after further forensic investigation involving the St. John the Baptist Parish Coroner’s Office, the Jefferson Parish Coroner’s Office, and the LSU Forensic Anthropology and Computer Enhancement Services Laboratory.

The cars crashed after smoke spreading through the region from a marsh fire east of New Orleans combined with thick fog and reduced visibility on highways to near nothing. The National Weather Service dubbed it a “super fog” — fog enhanced by smoke from damp, smoldering organic material. It can lower visibility to less than 10 feet (3 meters).