PORTLAND, Ore. (KOIN) — Officials are preparing for a “mass fatality incident” after Oregon wildfires have burned over 1 million acres this week and destroyed thousands of structures.

During a press conference with Gov. Kate Brown on Friday, Director of the Oregon Office of Emergency Management Andrew Phelps said they are preparing for a “mass fatality incident” based on the areas burned but did not yet have an accurate number of deaths to report.

“We know we’re dealing with fire related deaths and we’re preparing for a mass fatality incident based on what we know and the number of structures lost,” Phelps said.

“This is going to be a long term recovery operation,” he said. “The long term recovery is going to last years.” He said he knows this based on how California towns are recovering from recent devastating wildfires.

At least three fire deaths have been reported in Oregon so far, including that of a 12-year-old Lyons boy.

Brown said 40,000 Oregonians have been evacuated and 500,000 were in evacuation zones, clarifying data released by Oregon’s Office of Emergency Management on Thursday. She said more than 1 million acres have burned so far.

“We are doing everything we can to fight these fires,” she said.

“Thank you so much for taking care of each other. Thank you to our firefighters, our National Guard, and our Red Cross volunteers,” she said.

Brown said she was relieved that Oregon’s federal emergency declaration was approved, saying it will bring much needed resources to the state.

During the Friday update, Doug Grafe, Oregon Department of Forestry’s chief of fire protection, said cooler temperatures and moisture in the air help the fire fight.

“Great news on the front relative to the weather,” Grafe said. “This condition will carry through the weekend, so this is positive news.”

“We’re growing with more confidence that we will have moisture coming across the state,” he said.

Grafe said maintaining and establishing containment lines is the biggest challenge.

“We have a tremendous work load ahead of us.”

There are 16 fires currently burning in Oregon. Grafe said he expects eight of them to burn until “the winter rains fall.”

“To manage expectations, we will see smoke and have firefighters until the heavy rains fall,” he said.