The Oregon Department of Transportation said Interstate 84 was closed between Hood River and The Dalles

Hood River, a popular tourist destination about 89 kilometres east of Portland, is home to some 8,000 people, and more than 15,000 people live in The Dalles further east

Photos shared by the department showed flames burning alongside and in the median of the highway as wind gusts fanned smoke

A water-dropping helicopter and a plane dropping fire retardant helped fight the fire from above. The fire broke out on Wednesday

Department spokesperson David House said in an email that the interstate will be closed indefinitely, "due not only to the wildfires but also due to the extreme danger of driving in smoke"

Residents of more than 700 homes were ordered to evacuate in an area stretching northwest of The Dalles along I-84 and further inland, according to the Wasco County Sheriff's Office. Residents of more 1,352 homes were told to prepare to leave, including in part of the town's northern end

Two temporary shelters, including one at a middle school, are set to be opened in The Dalles, the sheriff's office said

Washington state's transportation department said a separate brush fire has closed 13 kilometres of State Route 14, which also runs along the Columbia River

Authorities urged people travelling in the area to use alternate routes