Republican presidential candidate Ben Carson might find himself on the receiving end of criticism once again after he compared Americans' worry over Syrian refugees to the concern of parents about "mad dogs" in the neighbourhood.

"If there's a rabid dog running around in your neighbourhood, you're probably not going to assume something good about that dog, and you're probably going to put your children out of the way," he said while he was in Mobile, Alabama, according to NBC News.

"(It) doesn't mean that you hate all dogs, by any stretch of the imagination, but you're putting your intellect into motion and you're thinking 'How do I protect my children? At the same time, I love dogs and I'm gonna call the humane society and hopefully they can come take this dog away and create a safe environment once again,'" said.

Carson said in this situation there is a need to immediately take out the "mad dogs" to protect the people.

"We have to have in place screening mechanisms that allow us to determine who the mad dogs are, quite frankly," he said. "Who are the people that want to come in here and hurt us and want to destroy us? Until we know how to do that, just like it would be foolish to put your child out in the neighbourhood knowing that that was going on."

Many of the 2016 presidential hopefuls and several governors nationwide have made an appeal for the country to bar the entry of Syrian refugees into America in light of the Paris terror attacks as they expressed fears that terrorists could sneak into the country in the guise of refugees.

Carson considers the Islamic State (ISIS) as a "much greater" threat to the United States than al Qaeda, the terrorist group responsible for the Sept. 11, 2001 attacks on the U.S. which, according to Carson, "really didn't require a great deal of sophistication" back then.

"You had to be able to fly some planes and get a couple of people in here. That's going to be a lot more difficult now," he said.