India, Sept. 5 -- Residents in Denver, Aurora, Thornton, and Arvada, Colorado, have reported heavy smoke and hazy skies, raising concerns about a possible nearby fire.

One person wrote, "Is there something burning near Lowry? Very very Smokey all of a sudden; thanks."

Another asked, "Where is the smoke/haze coming from? Smells like burnt rubber."

A third person wrote, "The smoke is here and its getting nasty outside. We just finished eating outside a few minutes ago as the thicker smoke moved in from the north and you could certainly smell it!"

As of now, Denver's Air Quality Index (AQI) is at 84, which falls in the "moderate" range, but residents are advised to limit prolonged outdoor activity if sensitive to air pollution.

Authorit...