Donald Trump Argues Many in US Share 'Same Feeling of Hate' as Terrorists Behind Brussels Attack It used "to be a safe and beautiful city," before "it really changed," he says.

 -- In an interview with "Good Morning America,"Donald Trump called this morning's deadly terrorist bombing in Brussels a "horrible attack," adding that he would be "hitting ISIS so hard" if he were president.

"You've got to take them out," Trump said of the terrorist group that claimed responsibility for the terrorist attacks in Paris last year. "And you've got to get the people, the surrounding states, you've got to get them to put up the manpower because that's what it's going to take.

"We have a lot of people in our country right now that probably and definitely have the same feelings and the same feeling of hate as the people in Brussels," Trump argued.

Trump also said, "I was in Brussels many times over the years. And it used to be a safe and beautiful city. And then it really changed."

Trump called the Belgium capital "like an armed camp. Anybody that goes there will tell you it's like an armed camp."

Trump continued, "And Brussels is different and Paris is different and lots of places are different. And the police don't have control of it anymore. And it's a very sad thing to see what's happening. “

The GOP presidential front-runner also tweeted today that the United States must be "vigilant and smart," specifying on “GMA” that he means the U.S. should "strengthen up our borders. We'd be very careful who we allow into our country."

There were two explosions in the departure hall of Brussels Airport in Zaventem, Belgium, this morning, according to Prime Minister Charles Michel. There was also an explosion on the rail tracks at the Maelbeek subway station, according to a spokeswoman for Brussels transportation department.