Authorities declared an environmental emergency on Tuesday for metropolitan Mexico City, one of the world’s most populous megalopolises, as smoke from nearby wildfires pushed pollution to levels deemed potentially harmful to human health.
Environmental authorities advised residents to avoid outdoor activities and exercise and remain indoors with windows and doors shut. It called for especially sensitive groups, including infants, the elderly and sick, to stay at home.
The local government said later that the circulation of vehicles would be restricted for most of Wednesday.
The Mexican capital is home to nearly 9 million people, with more than 21 million . . .
