Chicago, United States:
A fire apparently set by an employee at a Chicago-area air traffic control center led to the cancellation of nearly 1,700 flights at the city's two major airports, snarling air traffic across the United States, officials said.
Flights resumed at O'Hare International Airport, one of the world's busiest, after a delay of about four hours, but there were bottlenecks across the entire air system.
The blaze at the facility in Aurora, outside of Chicago, appeared to be set by a man who suffered self-inflicted knife wounds, Aurora police said. There were no indications that it was an act of terrorism and the blaze was quickly extinguished, they said.
The suspect was identified as a 36-year-old man who was apprehended in a minor struggle and is expected to survive his injuries. Law enforcement officials at a news conference said it was an isolated incident.
"We don't know what the motive was at this time," said Tom Ahern, a spokesman for the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives. No criminal charges have yet been made.
The incident caused major delays at O'Hare and the domestic hub Midway International Airport, affecting flights from almost every state and routes with Europe, Asia and Latin America.
Local broadcaster WGN quoted unidentified law enforcement officials as saying the suspect was a disgruntled employee who tried to sabotage the center, which is crucial for air traffic.
The man entered the building's basement and cut wires for air traffic control equipment and also doused the wires with gasoline and set them on fire, WGN reported.
There were 1,675 flights into and out of the two airports that were canceled by 2:20 p.m. CDT (1920 GMT), according to tracking website flightaware.com, leaving thousands of travelers stranded.
"There's cascading delays because nothing can take off bound for Chicago from anywhere," said Doug Church, spokesman for the National Air Traffic Controllers Association, a union of air traffic controllers. "The impact is national and major."
DELAYS THROUGH THE DAYAt O'Hare, passengers were scrambling to find alternative transportation or bracing for long delays.
"I'm shocked at how calm everyone is. With everything going on in the world, maybe we're all managing our expectations. It's a fire in Aurora, it's not ISIS," said Cynthia Stemler of the Chicago suburb of Lake Bluff, who was heading to Newark, New Jersey, in a reference to the militant Islamic group at war in Syria and Iraq.
O'Hare is the main hub for United Airlines and a major hub for American Airlines. From January to August, more than 580,000 flights departed or landed at O'Hare, the city of Chicago said, citing Federal Aviation Administration data.
Southwest Airlines Co suspended all flights through the day at Midway and Milwaukee's General Mitchell International Airport, the airline said in a statement.
The FAA said employees were evacuated from its control center in Aurora when the fire broke out, reportedly at about 6 a.m. CDT (1100 GMT).
Airspace management was transferred to adjacent air traffic facilities, the FAA said.
Crews responding to the fire in the facility's basement found the wounded man, who was transported to a hospital, the Aurora Police Department said. One other person was treated for smoke inhalation.
There was no explosion and the fire likely spread through the use of an accelerant, police said.
On May 13, about 700 flights were canceled at O'Hare and Midway airports after a faulty motor in the heating and cooling system at a flight control center in Elgin, Illinois, a Chicago suburb, caused smoke to circulate and forced staff to clear out of the building.
© Thomson Reuters 2014