MidAmerica Airport reopened flights at 5 p.m. Sunday after closing for more than three hours while authorities investigated a suspicious item.
A carry-on laptop taken through security had "suspicious wires" in it, prompting a partial evacuation of the boarding area, according to Capt. Bruce Fleshren with the St. Clair County Sheriff's Department.
As of 5 p.m. Sunday, the airport opened for normal traffic. Flights to Destin, Jacksonville and Fort Lauderdale were canceled. Flights to Las Vegas, Orlando, Daytona Beach and Punta Gorda were delayed.
The suspicious item was found to be harmless, Fleshren said. It was a laptop with a hard drive attached.
Passengers were moved from the boarding area to another part of the terminal after Transportation Security Administration officials secured the laptop, Fleshren said. The Illinois Secretary of State Police bomb squad was contacted to inspect the laptop.
Several hundred people were standing around in the pre-security area, waiting to hear news on the scare.
Anna Carey, who was heading back to Jacksonville, Florida, after visiting her parents in Missouri, said she wasn't too bothered by the delay.
"I'm traveling by myself, so it's really fine," Carey said. "They have to do what they have to do ... It's just something that happens I guess."
Courtney Johnson, who flew in to MidAmerica from Orlando, Florida, said her plane had been sitting on the tarmac since about 2 p.m. Sunday, waiting for a gate. Crews on board Johnson's flight told passengers they were still on board the plane for their safety.
Allegiant responded to multiple people's tweets Sunday, explaining what was going on and thanking them for their patience.
MidAmerica Airport tweeted at about 4:30 p.m., about three hours after the investigation began.
"We appreciate all of our travelers and their patience today while the authorities do what is needed to make it safe for all flights resume," the tweet read.