A wildfire in eastern Arizona continues to burn, expanding to over 20,000 acres, with more red flag warnings in effect on Monday.

The Greer Fire, named after the small community in Arizona’s White Mountains where the blaze sparked on May 13, has grown to 20,425 acres and is 38% contained, officials said on Monday.

A red flag warning in northeastern Arizona — including the area of the flames — is in effect on Monday, with officials urging residents to avoid burning or using tools that spark.

“One spark into the dry veg under red flag conditions can start a rapid spreading wildfire,” the Arizona Department of Forestry and Fire Management said Monday in a post on X.

Over 700 personnel have been assigned to battle the blaze, with high winds — reaching around 40 mph — posing “another test for firefighters holding the firelines,” the forestry service said.

On Saturday, Arizona Gov. Katie Hobbs declared a state of emergency in Apache County due to the growing flames.

“My heart is with everybody who has been impacted by this devastating wildfire,” Hobbs said in a statement on Saturday.

Evacuations have been issued for Greer, South Fork, residents west of Highway 261, Eager, south of Highway 260 and west of River Road, officials said. An interactive map has also been established to highlight the current evacuation orders.

The cause of the fire remains under investigation, officials said.

Greer is a small mountain town near the state’s border with New Mexico with a population of less than 60 residents, as of 2020 census data.

More information on the growth of the fire and evacuations will be provided to the public on Monday evening, the forestry service said.

ABC News’ Leah Sarnoff contributed to this report.