BUENOS AIRES — A curtain of smoke from burning rural fields settled over this Argentine capital Thursday, delaying flights, shutting roads and leaving residents coughing.
The influx of smoke blown toward the capital by prevailing winds also reignited hard feelings between the government and the nation's powerful farming industry, which recently suspended a three-week strike against new taxes on grain exports.
"We are facing a disaster caused by man with lamentable consequences," Interior Minister Florencio Randazzo said.
The smoke originated from hundreds of fires consuming more than 150,000 acres of grasslands about 120 miles northwest of the city, officials said. Farmers in South America routinely use fires to clear land for new plantings and to remove scrub. But authorities said some fires were now burning out of control.
Authorities said they were investigating to see whether the fires violated environmental laws, even if the blazes were set on private property. Some fires have apparently been burning for days. Firefighters were working to douse the fires, using air tankers, helicopters and fire engines
A thick haze covered the city in the morning, dispersed somewhat in the afternoon but returned in the evening. Television reports covered the situation as a national emergency.
Limited road visibility from a combination of smoke and fog was blamed for a traffic accident outside the city that left four people dead. The smoke caused service on some bus routes to be canceled and disrupted air and car traffic.
There were also reports of increased numbers of people seeking treatment for eye and throat irritations from the haze, which permeated buildings and left many homes reeking of smoke. The scent of distant fires was ubiquitous. The downtown Obelisk, a capital landmark, was obscured in the early evening.
"I feel very bad because of the smoke since last night," said Horacio Quillay, 28, one of a number of people interviewed at a popular park in the Palermo district. "My throat hurts. I have a cough."
Physicians said there was no immediate health risk, but people with respiratory and eye problems were advised to take precautions, such as putting a cloth over their mouths and noses to breathe.
"My eyes have been burning all day," said Juliana Alvarez, 19. "They bothered me watching TV and in front of the computer."
Such rural fires are a seasonal phenomenon, but the smoke seldom reaches metropolitan Buenos Aires, home to more than 12 million people. Authorities said a combination of larger-than-usual fires, winds from the north and a thermal inversion could have combined to create the noxious atmospheric soup.
President Cristina Fernandez de Kirchner compared the situation to a 1991 volcanic eruption that sent dust over the southern Argentine province of Santa Cruz, obscuring daylight.
"But this wasn't a natural disaster," Fernandez said. "This was the work of some aspects of human nature, irrationality and irresponsibility."
A poll by the Buenos Aires daily Clarin asked readers whether they had felt the effects of the smoke. Nearly nine in 10 responded that they had.