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NORTH TEXAS (CBSDFW.COM) – Expect extra security if you’re flying out of North Texas on Wednesday.

The Transportation Security Administration (TSA) is placing additional officers to airports in major U.S. cities in the wake of the terror attacks in Belgium.

Wednesday morning started out quietly at DFW International Airport. Some passengers arrived early for their flights. The beefed up security was evident as armed officers, including K-9 units and bicycle officers, patrolled the check-in area, and a busload of TSA employees were dropped off at the terminal.

The U.S. State Department is now warning American citizens traveling in Europe to be vigilant. Officials are of the belief that terrorist groups will continue to plan attacks that target public places. The State Department’s website says, “Terrorist groups continue to plan near-term attacks throughout Europe, targeting sporting events, tourist sites, restaurants, and transportation.”

Airline passengers arriving at DFW International Airport from Paris on Tuesday night said that they did not learn about the attacks until the plane had landed. Passengers said that there was no mention of the attacks while in the air.

Once on the ground, Stephanie Simpson noticed that things were a little different. “They had heightened security,” she said, “and I had to go through an extra long [security] line.”

The Department of Homeland Security is stressing that there is no specific, credible intelligence pointing to a similar plot in the United States.

Travelers on Wednesday morning said that they felt safe flying. “I’m okay with it. I think it’s alright,” said Mimi Rogers on her way to Colorado. “We did get here a little early though.”

“I didn’t really think about it that much,” added Jimmy Bonner, who was traveling to Mexico. “Unfortunately, it’s gotten to be such a common occurrence. You kind of feel desensitized to it. It’s always in the back of your mind, but if you let that start dictating what you do, you don’t get to do anything.”

American Airlines has cancelled all flights in and out of Brussels for Wednesday and Thursday. The airline is still scheduled to operate a flight from Philadelphia to Brussels on Friday, with a return on Saturday. But that could change, depending on when the airport in Brussels reopens.

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