Chicago's O'Hare International Airport's Terminal 1 was reopened on Wednesday morning after an evacuation that lasted almost two hours while a police bomb squad investigated a report of an unattended bag, police said.
"Everything's clear; the terminal is reopened; no explosives were found," said a Chicago Police Department spokeswoman.
The terminal was evacuated and some United Airlines flights delayed as the police investigated an unattended bag that was found at about 9:30 a.m. local time, the city's aviation department and local media reports said.
United Airlines in a statement encouraged customers traveling out of O'Hare to check their flight status and allow extra time for security screening.
O'Hare is the second busiest airport in the United States, for passenger traffic.