A United Airlines spokesman says a search of a terminal where an intruder ran past a security checkpoint has turned up nothing.
Some 6,000 people were forced to exit the terminal and had to wait outside during the search. Police say they uncovered nothing suspicious, reports CBS station WBBM-TV in Chicago.
Spokesman Joe Hopkins says the first of the thousands of people who were evacuated from a terminal were let back inside, and flights were resumed.
United is still trying to recover its schedule from the ordeal. At least 120 flights were canceled and at least 200 more were delayed. The airline says about 27,000 passengers nationwide were affected by the problem. Some had to sit on planes for hours on airport tarmacs in Chicago and other cities.
Only United flights were affected because the security breach occurred in a terminal used exclusively by United.
Travelers can expect delays even Friday, reports CBS News Correspondent Cynthia Bowers.
Police described the intruder as a white man about 6 feet tall and about 160 pounds, with a bushy mustache. He was carrying a canvas bag, police spokesman Patrick Camden said.
|Planes delayed by security breach at O'Hare Airport wait on tarmac.|
Airport and airline officials say they still don't know whether the man who started it all had evil intent or was simply late for his plane.
Federal Aviation Administration investigators are examining surveillance video tapeshot at the moment the man ran past the security guard, past the "Do Not Enter" sign, and up the down escalator.
A woman whose flight was postponed told WBBM-TV that "They really didn't tell us much. They didn't tell us anyone was on the loose Â… I heard it through word of mouth."
The intruder had just departed for a flight at about 3 p.m. when he turned back and ran from a baggage claim area up a one-way staircase to a concourse, said United spokesman Matthew Triaca. Guards are stationed at the staircase.
Hopkins said the search focused on suspicious packages that may have been left in the terminal.
The scare is not the first sign that security operations are on a hair trigger at U.S. airports. It was just three weeks ago a Delta jet was stopped, cleared of 241 passengers and searched because one passenger was acting suspiciouly on the eve of the anniversary of the embassy bombings in Africa. In Chicago, it was a judgment call that led to numerous calls for an explanation.
"It was a terrible inconvenience. In the interest of the safety and security of our passengers, it was the right decision to make," said Mary Rose Loney of the Chicago Aviation Authority.
In U.S. airports, it seems the price for security will be fewer freedoms and more delays.