Updated

Fires allegedly set by farmers sent clouds of smoke across the Argentine capital on Thursday, disrupting air and highway travel and choking millions of Argentines.

Some 270 square miles have burned in recent days, according to Interior Minister Florencio Randazzo.

"We are facing a disaster caused by the hand of man," he said Thursday.

The smoke forced air traffic controllers to cancel landings at airports in Buenos Aires and led police to close some major highways. Some bus routes were scrapped for lack of visibility.

Randazzo and other officials accuse private farmers of setting the blazes to cheaply clear scrub from grazing land.

Environment Secretary Romina Picolotti said that the situation poses potential health risks. Authorities reported a steep increase in the number of people seeking attention at hospitals with eye problems.

Randazzo said the government has asked prosecutors to prosecute those who set the blazes.

"Burning pastures is a crime," she said.