No threat was found at Denver International Airport after an evacuation of a section of the main terminal because of potentially suspicious packages.

Denver police cleared a part of the main terminal on the west side between doors 600 and 610 on level six and 500 to 510 on level five, according to an airport tweet. Level five is the bag claim and passenger pickup level, and level six is for passenger dropoff and check-in.

The terminal re-opened to the public just after 4:45 p.m.

Airport officials said "several packages"were screened to determine the validity of the threat that was originally reported by TSA.

Denver police spokesman Sonny Jackson said the alert was "strong enough" to prompt an evacuation and full response.

Airport officials did not make any ties or connections to the terrorist attacks in Brussels.

"We are just looking at this particular incident," officials said. "We would respond like this on any day."

Denver International Airport
© Wikimedia CommonsDenver International Airport in Denver, Colorado, United States.
Travelers are being asked to check with their airlines to see if their flight has been delayed because of the incident. Flights are continuing, the airport said, although delays are possible.

"As a precaution, TSA is deploying additional security to major U.S. airports and at various rail and transit stations," said a tweet from Homeland Security Secretary Jeh Johnson.

Vehicle traffic was not allowed on the west side of the terminal for a while, but it too has opened, officials said.

Airlines were working to resume baggage delivery to their normal locations.

Ryan Hitchler was in concourse C of the airport and said there was "no notice whatsoever" of the disturbance in that area. His flight was on time, he said.

Major cities across the nation have been on heightened alert Tuesday in the wake of terrorist attacks in Brussels.

The Denver airport said earlier it was not instructed by the Transportation Security Administration or the Department of Homeland Security to increase any security measures after the Brussels attacks that left dozens dead.