Authorities are investigating the possibility of arson as the cause of a deadly wildfire in western Oklahoma.

The Dewey County Sheriff's Office said Friday it is investigating a fire that broke out April 12, killing a woman that was found inside a burned vehicle Saturday near Seiling, Oklahoma, the Associated Press reports.

A second death was also reported in connection with wildfires in the Sooner State: a 61-year-old man who died last Thursday in a fire in Roger Mills County.

(PHOTOS: Deadly Plains Wildfires, in Pictures)

Conditions remained dangerous Friday in the Plains as firefighters continued to battle two large wildfires in Oklahoma.

According to the AP, fire crews in eastern Arizona are combatting a human-caused fire in a remote area of the Apache-Sitgreaves National Forests that had burned 20 square miles and is 20 percent contained. In New Mexico, a fire that began Friday afternoon in Socorro County forced the closure of State Highway 116 and threatened 10 to 15 homes.

There is some good news, though, according to weather.com senior meteorologist Jon Erdman.

"Rain and thunderstorms will spread over the parched southern Plains Friday into Saturday," said Erdman. "At least an inch of rain is expected in parts of south-central Kansas into central Oklahoma. The panhandles of Texas and Oklahoma may see their most significant rain event in six months." 

For residents in Oklahoma, conditions began to improve Thursday from earlier in the week, when aggressive grass fires destroyed homes in the Sooner State as well as in Colorado amid some of the most extreme fire conditions in years.

In western Oklahoma, a blaze dubbed the Rhea Fire has burned more than 450 square miles — an area larger than New York City. It has destroyed at least 50 homes and forced hundreds of people to evacuate in Dewey County since Thursday, according to fire officials. The conflagration was just 29 percent contained as of Friday night.

Starting Tuesday night, some towns in western Oklahoma told residents to not call 911 unless they're reporting a fire, the AP also said. A state of emergency was declared by Gov. Mary Fallin for 52 counties.

A wildfire in Colorado near Fruita in western Colorado closed a section of I-70 Thursday and Friday morning. The fire is believed to have been sparked by a campfire on Wednesday, the Associated Press reports. The interstate reopened several hours later. 

At least 23 homes were destroyed by a blaze that started Tuesday between Colorado Springs and Pueblo, El Paso County Sheriff Bill Elder told the AP. The fire grew rapidly, torching 64 square miles, but no injuries were reported.A separate fire near Colorado Springs chased 200 families from their homes and destroyed at least five dwellings and several outbuildings, the AP also reported. It's not believed anyone was hurt by the wind-driven wildfire.

Both fires in Colorado are now contained, reports Inciweb. 

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In Kansas, the State Emergency Operations Center was activated due to the fire weather conditions, which officials warned were still extreme despite recent rain and snowfall, the AP reported.

As a fire crossed into Kansas from Colorado Tuesday night, some 90 homes were evacuated, the AP also said. By Wednesday morning, the fire had been contained and no injuries were reported, state emergency management spokeswoman Katie Horner told the AP.

As a response to the fires, Kansas Gov. Jeff Colyer issued a disaster declaration.