America's enemies witnessed the "massive vulnerability" in security at the U.S. Capitol Wednesday after rioters stormed the halls of Congress and sparred with police, Sean Hannity said Thursday.

 "We must determine what went wrong at the U.S. Capitol, that is our top priority," the "Hannity" host said. "Americans demand answers, rightly so. What we all witnessed yesterday inside the Capitol building, that could never, ever, ever happen again in this country. That building belongs to we the people. This is our house and it was breached, and it was breached within minutes with relative ease ... it's inexplicable."

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Hannity's comments came hours after Capitol Police Chief Steven Sund announced his resignation and a day after protesters breached the Capitol, overran his officers and prompted condemnation from lawmakers on both sides of the aisle in Washington.

"They knew that hundreds of thousands of Americans had, in fact, descended upon Washington yesterday," Hannity said. "They knew what their plan was, to march from the Washington Monument to the Capitol. They knew Congress would be in session."

The breach sent a resounding message to "every one of America’s enemies" who witnessed this "massive vulnerability," Hannity explained.

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"I was shocked, I couldn’t believe within a minute, two minutes, they were in. Now they see our Capitol building is wide open. What if Al Qaeda, what if ISIS terrorists were among those that breached that the building yesterday? That is a nightmare scenario."

Hannity went on to call for a "full, transparent investigation of what went wrong and who screwed up."