NEW ORLEANS (AP) At least seven people were killed after a superfog of smoke from south Louisiana marsh fires and dense fog caused multiple massive car crashes Monday morning involving a total of 158 vehicles, authorities said.

Twenty-five people were injured and the number of fatalities may increase as first responders continue to clear the crash scenes and search for victims, Louisiana State Police said in a press release Monday evening.

Gov. John Bel Edwards issued a call for blood donors and asked for prayers for those hurt and killed.

Videos of the wreck showed what looked like an endless junkyard of cars overtaking the busy interstate near the community of Manchac. Vehicles were crushed, rammed under one another and some were engulfed by flames. Many people stood on the side of the road looking in disbelief at the disastrous scene, while others remained in their car waiting for aid.