Five months after a devastating wildfire destroyed hundreds of structures in the Town of Slave Lake, officials say the wildfire investigation has determined arson as the likely cause.

Sustainable Resource Development (SRD) Minister Frank Oberle says their investigation into the cause of the fire ruled out everything but arson as a probable cause.

"We arrived at that conclusion by a process of eliminating all other possible causes," Oberle told media Tuesday. "We know there was no lightning at that site, we know there was no powerline malfunction, no campfire location at that site,

"Our investigation eliminated all natural, industrial or accidental causes."

The province has turned over all files and reports related to its investigation to the RCMP.

The 4,700-hectare fire began on May 14th, and caused 7,000 Slave Lake and area residents to be evacuated. The blaze eventually destroyed about 400 structures, mostly homes.

The minister confirmed his department was able to pinpoint exactly where the fire started but can't reveal that because it is now the focus of a criminal investigation.

This was one of three wildfires burning near Slave Lake back in May.

And in terms of the other two fires, the minister says at this point it appears those fires were not likely caused by arson.

The Mayor of Slave Lake spoke to the media Tuesday, and asked the citizens of Slave Lake to remain calm at this new development, and focus on rebuilding the community.

"I'm not angry, we've lost what we've lost and we can't bring that back," Mayor Karina Pillay-Kinnee said. "It's important that we focused on…the recovery, on the rebuild."

The province says the wildfire caused an estimated $700 million in damages -- the second-most-costly insured-damage disaster in Canadian history, behind the Quebec ice storm of 1998.

With files from Laura Tupper and Sean Amato