CHICAGO (AP) — A tornado touched down Wednesday evening near Chicago’s O’Hare International Airport, prompting passengers to take shelter and disrupting hundreds of flights. There were no immediate reports of injuries.

A confirmed tornado was on the ground around 7 p.m., according to the National Weather Service in Chicago.

“This tornado has been touching the ground intermittently so far and is moving east. There are additional circulations along the line south of O’Hare. Seek shelter if in the warned area," it said.

By 8 p.m. the weather service said the Chicago forecast area was “currently tornado warning free." It said the storm was moving east toward southwest Michigan, and a tornado watch was in effect into Thursday morning for parts of Michigan, Indiana and Ohio.

Video from TV stations showed hundreds of people taking shelter in an O’Hare concourse. Some 173 flights departing the airport were canceled and more than 500 were delayed, according to the flight tracking service FlightAware.

Kevin Bargnes, director of communications for O’Hare and Chicago Midway International Airport, told WGN-TV Wednesday night that no damage was reported at either airport.

The National Weather Service had issued two tornado warnings for Chicago Wednesday evening. Tornado sirens sounded warning people to find shelter.

Lynn Becker, a longtime Chicago resident, posted video to Twitter with tornado sirens blaring across the city’s iconic skyline.

“I’m in a 60 story apartment building so my options are somewhat limited,” he said. “We have to, I assume, go into the core of the building.”

Becker said news of the storm was featured across local media.

“There’s a certain panic when you’re watching a TV screen and everything is in red … but the hope is that the damage is minimal,” he said.

Local news outlets said warehouses were reportedly damaged near O'Hare.

The weather service quoted an unidentified emergency manager as saying a roof was blown off in the community of Huntley in McHenry County northwest of Chicago. Huntley Battalion Chief Mike Pierce told ABC-7-TV that firefighters and other emergency services were responding to downed power lines, trees and tree branches, and that power outages had been reported. Building damage appeared to be concentrated around two apartment buildings, he said.

More than 10,000 customers lost power in the region, according to poweroutage.us.

In Hodgkins, southwest of Chicago, police said storm damage and debris was found on the north end of town, near a shopping center.

Earlier Wednesday, the weather service's Storm Prediction Center had said there was an enhanced risk for severe weather, including tornadoes in northern Illinois, including Chicago.

Brett Borchardt, senior meteorologist with the National Weather Service, confirmed to WGN-TV that multiple tornadoes touched down across the Chicago area. He said surveying the damage will likely take days.

Over the years many tornadoes have struck in the Chicago metropolitan area, and several have hit within the city limits of Chicago, according to the National Weather Service. Between 1855 and 2021, the weather service recorded 97 significant tornadoes in the Chicago metro area.

The deadliest formed in Palos Hills in Cook County on April 21, 1967. The twister traveled 16 miles (26 kilometers) through Oak Lawn and the south side of Chicago, killing 33 people, injuring 500 and causing more than $50 million in damage, according to the weather service.

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