Officials warned young children and those with respiratory illnesses to take precautions. For weeks, smoke from Canadian wildfires has been drifting across the border.

New York was hit with an air quality alert Saturday as smoke from Canadian wildfires drifted across the state, pushing levels of fine particulate pollution into the unhealthy range for sensitive groups.

The air quality index (AQI) is predicted to be above 100 in much of New York state on Saturday, and could reach 135. Alerts are also in place for parts of New England. The AQI measures the severity of pollution in the air and categorises health risks. The higher the number, the more unsafe the air is to breathe.