How a pro-Trump mob stormed the U.S. Capitol

Shattered glass and broken furniture littered the U.S. Capitol after a pro-Trump mob stormed the heart of government, wreaking havoc as lawmakers hid inside.

It was an unprecedented breach on Wednesday that current and former law enforcement officials told Reuters represents one of the gravest security lapses in recent U.S. history.

The bloody chaos came after Capitol Police were overrun by angry Trump supporters in what law enforcement officials called a catastrophic failure to prepare.

But Wednesday's events were preceded by weeks of online threats that the protests could descend into violence.

Many who traveled to the capital shared plans using websites such as Parler, a Twitter-like service that has attracted right-wing extremist groups. Some users discussed ways to illegally sneak guns into Washington.

While on Twitter, starting Jan. 1, there were nearly 1,500 posts from accounts related to the QAnon conspiracy theory movement that mentioned the rally and contained references to violence, according to a former intelligence official who monitors extremists on social media. These included posts urging so-called "Patriots" to "Rise Up.”

Despite those rumblings of danger, the Capitol Police force did not request advance help from other federal agencies such as the Department of Homeland Security --- to secure the building, according to one senior official.

And National Guard reinforcements, summoned by the city’s mayor, were not mobilized until more than an hour after protesters had first breached the barricades.

In stark contrast, those agencies were aggressively deployed by the Trump administration during last summer’s protests against police brutality in Washington and across the U.S.

In the aftermath of the breach, House Speaker Nancy Pelosi said she's called for the resignation of the chief of US Capitol Police. But says it goes beyond that.

"It goes to the FBI, what was the shortcoming in their intelligence provided. It goes to many other elements and we have to have a full review."

68 arrests have been made related to the breach, most of those were made on Capitol grounds, according to D.C. police chief, Robert Contee, who added they are not finished.

"We still have a significant amount of work ahead of us to identify and hold each and every one of the violent mob accountable. We have collected numerous. Images of persons of interest that we are asking the community to help us identify."

The FBI is also seeking help in identifying those involved in the breach.

For at least the next 30 days, the Secretary of the Army said there will be a 7 foot non-scalable wall erected around the Capitol.