BOSTON (WBZ NewsRadio) — A blanket of thick haze covered much of Massachusetts on Monday afternoon, setting off alarm bells from environmental authorities and the public.

The National Weather Service and the state Department of Environmental Protection (MassDEP) issued an Air Quality Alert for most of the state besides Cape Cod, the Islands, and southeastern Massachusetts. The alert was set to end at midnight.

The smoke, caused by wildfires in the western U.S. and Canada, left the Boston skyline completely obscured.

"All that smoke is sort of being lofted eastward," said National Weather Service Meteorologist Andrew Locanto.

The haze caused "unhealthy" air quality for cities across Western and Central Mass. like Worcester, Chelmsford and Springfield, according to the DEP. Residents were cautioned to stay indoors if possible, especially people with heart and lung problems, older adults, children and teenagers.

Members of the public were concerned, with many believing the smoke was from a local fire. Fire departments in Cambridge, Hubbardston, Northborough, and the state Fire Marshal's Office all received multiple calls about smoke in the area.

The departments were quick to clarify that the smoke was from out west and not any local house fires.

WBZ's Shari Small (@ShariSmallNews) has more on the haze with a National Weather Service meteorologist:

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