PORTLAND, Ore. (KOIN) — The Multnomah County Medical Examiner reported Sunday the number of deaths from the recent heat wave rose to 64.

The deaths were identified between June 27 and July 3, 2021, officials reported. Of the deaths, 30 have been formally ruled hyperthermia, or death by excessive heat. The remaining cases are suspected hyperthermia.

Multnomah County Chair Deborah Kafoury said the County will be conducting a much deeper analysis of what happened during the historic heat wave and how to plan for the future.

“Death investigators are continuing to respond to suspected cases in what has been an unprecedented mass casualty event,” county health officials said in a release Sunday. “They will be conducting additional investigation to bring what is still a very blurry picture into sharp focus.”

The preliminary data shows those who died from the heat in Multnomah County were aged 44 to 97, with an average age of 68. The majority were white. Many were found in their homes, with no air conditioning or fans, officials said.

Because several of casualties are suspected to be among the homeless population, health officials said they cannot release the exact number of deaths yet. 

Hundreds are believed to have died from the heat over the past week in the U.S. Northwest and southwestern Canada — more than 100 died in Oregon alone.

Records included 116 degrees Fahrenheit (47 degrees Celsius) in Portland and 108 F (42 C) in Seattle. The hot weather was headed east, with temperatures well above 100 F (38 C) forecast Sunday for parts of Idaho and eastern Montana.