LINCOLN, Neb. (AP) — Eastern Nebraska health officials have issued a warning about the potentially harmful levels of smoke in the air from agricultural burning.

The health departments in both Lincoln-Lancaster and Douglas counties issued a health advisory Friday for people with asthma, lung disease and other respiratory or heart conditions. Health officials say the source of the smoke is fires in the Flint Hills area of Kansas, several hours south of the Omaha metro area.

The notice applies to adults as well as children, and anyone with these health issues are advised to stay indoors with doors and windows closed.

Lincoln-Lancaster air quality supervisor Chris Schroeder says the area will likely be blanketed in the smoke for several days.