The Department of Natural Resources says it still hasn't determined the cause of the summer forest fire near Wabush.

An investigation into the month-long fire found where the blaze originated, but not how.

The fire started 11 kilometres from the town of Wabush, where people were clearing land the weekend of the fire.

The flames quickly spread, and lead to the eventual evacuation of the 1,800 residents in Wabush to neighbouring Labrador City.

Air quality concerns were cited as the main reason for evacuation.

More than 60 cabins in the area burned down in the fire.

The province estimates it spent more than $2 million to put the fire out.