Wildfire smoke from nearby marsh fires and heavy fog mixed to produce a “superfog” event early Tuesday morning northeast of New Orleans near the Irish Bayou, creating near-zero visibility conditions for drivers on Interstate-10.

Multiple accidents occurred in the area, resulting in one death, the New Orleans Police Department said in an emailed statement. Several victims were taken to the hospital, and sections of I-10 were closed in both directions.

Conditions became undrivable within minutes, overwhelming motorists with severely limited visibility from 4 a.m. to 7 a.m. local time. The National Weather Service warned drivers to stay off the roads and issued a dense fog advisory through 10 a.m. for eastern New Orleans and southeast St. Tammany parishes.