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A new Senate report reveals previously unknown details about the stunning security breakdowns ahead of the January 6 US Capitol attack, including a finding that the US Capitol Police’s main intelligence unit “was aware of the potential for violence” beforehand.

The report adds an authoritative emphasis to previous evidence that there were massive intelligence failures, critical miscommunications, and unheeded warnings that ultimately led to the chaotic response that day.

RELATED: Takeaways from the Senate report on January 6 security failures

Among the failures was an inability by intelligence officials to tie together a swirl of troubling internet chatter leading up to the riot and a reliance on using past, non-violent Trump rallies in security planning.

There are also several glaring omissions in the report including any examination of Donald Trump’s role in the riots, raising questions about whether lawmakers, in their quest for bipartisanship, exposed the limits of a Congress divided and unable to agree on certain truths, particularly those related to the former President’s actions.

READ: Bipartisan Senate report investigating January 6 Capitol attack

Sources tell CNN that in order for this report, which was compiled by the Senate Homeland Security and Rules committees, to have support from both parties, the language had to be carefully crafted, and that included excluding the word “insurrection,” which notably does not appear outside of witness quotes and footnotes.

“Did we look at Trump’s role in the attack? The answer is no,” a Senate committee aide told reporters.

“The report did not attempt to look at the origins and development of the groups or individuals that participated in the attack on the Capitol,” the aide said.

Still, it marks the most comprehensive government report on the security failures leading up to the Capitol insurrection. Congressional investigators pored through “thousands of documents,” received written statements from 50 police officers who defended the Capitol, and got testimony from a wide array of current and former officials who played a role in the security preparations and response.

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New details about extent of communication among rioters

Trump supporters posted plenty of violent threats and dangerous assertions on the internet in the run-up to January 6. The report said these were found on “message boards, social media, memes, or hashtags.” But intelligence officials struggled with how to interpret warnings about those posts and how to differentiate between protected political speech and actual threats.

The aides said that the Senate probe did uncover new information about the extent of the communication beforehand among the rioters, including an increase in traffic to a website about Washington’s tunnels.

Aides were pressed on why, despite mounting evidence there were plans to attack the Capitol, law enforcement seemed to rely on past-MAGA marches that remained largely non-violent. The aides said the law enforcement intelligence focused on clashes between groups rather than violence toward a building.

The report also concluded that the Capitol Police’s main intelligence unit “was aware of the potential for violence in the days and weeks ahead of January 6.” But not everyone was aware. The inquiry determined that USCP’s “decentralized” intelligence operation meant some people saw these warnings while other officials were left in the dark.

WASHINGTON, DC - JANUARY 6: Pro-Trump protesters gather in front of the U.S. Capitol Building on January 6, 2021 in Washington, DC. Trump supporters gathered in the nation's capital to protest the ratification of President-elect Joe Biden's Electoral College victory over President Trump in the 2020 election. A pro-Trump mob later stormed the Capitol, breaking windows and clashing with police officers. Five people died as a result.  (Photo by Brent Stirton/Getty Images)
Capitol riot's toll on officers persists
03:08 - Source: CNN

In a statement, the Capitol Police said the intelligence reflected a “large demonstration attracting various groups, including some encouraging violence.”

However, the agency added, “What it didn’t know, as Acting Chief Pittman has noted, was the large-scale demonstration would become a large-scale attack on the Capitol Building – as there was no specific, credible intelligence about such an attack,” referring to acting US Capitol Police Chief Yogananda Pittman.

“Neither the USCP, nor the FBI, U.S. Secret Service, Metropolitan Police or our other law enforcement partners knew thousands of rioters were planning to attack the U.S. Capitol,” the agency added. “The known intelligence simply didn’t support that conclusion.”

Senate aides said the information from the report was pulled from a variety of sources – public hearings, private communications and five transcribed interviews, including with former acting Secretary of Defense Chris Miller and Pittman.

But there was clear frustration among the committees that not everyone cooperated fully with their information requests. The report gleaned heavily from information derived from the Capitol Police.

“We did develop some information with respect to DHS and FBI. It’s not that DHS and FBI withheld information. It’s that their response so far has been very partial and frankly unsatisfactory,” a Senate aide said.

Moreover, the Senate investigators ran into institutional hurdles – including from the House sergeant-at-arms, which did not provide information to the panels because “the House is sort of responsible for its own affairs, and the Senate is responsible for its own affairs,” an aide said.

Pittman provided significant testimony, both in an interview setting as well as in open hearings. However, the report notes apparent variations in her answers, something aides acknowledged but declined to explain further.

“You’ll see throughout the report significant quotes from acting Chief Pittman and we do point out places where there have been some perceived inconsistencies including with respect to the intelligence products,” the aide said.

Limits of a bipartisan congressional probe

The report’s narrow scope underscores the limits of a bipartisan, congressional investigation. While the evidence and interviews were gathered over months from bipartisan staff and members on two committees, the information pertained almost entirely to the security and intelligence shortcomings that led to that day, not focusing on why individuals would have come to the Capitol in the first place and Trump’s role.

Democratic Senate investigators took careful steps not to alienate their Republican counterparts in the process of the probe, which meant not taking a closer look at Trump’s role in promoting the Jan. 6 rally and months-long attempt to pressure local officials, lawmakers in Congress and then-Vice President Mike Pence to subvert the will of the electorate.

Aides also steered clear of language that could turn off some Republicans, including not referring to the attack as an “insurrection.”

“The language that was chosen was purposeful – and represents the consensus of the four members and their respective staffs,” a Senate committee aide said. “We did our very best to stick of the facts as we understood them and leave characterizations in quotes where there were characterizations.”

In one clear example of that, the report’s appendix includes Trump’s full speech before the January 6 crowd – but does not go further into interpreting how that influenced the Capitol rioters. A Senate aide said that decision was made to avoid inserting “our editorial judgment” of the speech.

RELATED: Republicans have downplayed the US Capitol riot violence. The evidence paints a different picture.

While the report did nod to some of Trump’s statements and tweets leading up to the events at the Capitol, the report did not fully explore the root causes of what led to an insurrection at the Capitol, nor did it lay blame on the former President directly for promoting a lie that the election was stolen that mobilized supporters to gather at the Capitol on January 6.

The conclusion of the congressional investigation comes weeks after the Senate rejected a bill from the House of Representatives that would have established a bipartisan commission to study the insurrection. That body would have been staffed by individuals outside of Congress and the administration. That investigation would have been far reaching and would have been tasked with exploring some of the events that may have been responsible for triggering the events of the insurrection. The bill, however, failed to gain traction in the Senate where just a handful of Republicans joined with Democrats to back it.

Sen. Rob Portman, a Republican from Ohio and the ranking member on the Homeland Security Committee who authored the congressional report Tuesday, voted to advance legislation that would have established the commission. But, Sen. Roy Blunt, a Republican from Missouri who served as the top GOP member on Rules, did not.

Blunt argued that the congressional report went far enough and provided the framework for how to make fixes to Capitol Hill security, which could be delayed if a commission were established.

“I think a commission would slow down the things we need to do,” Blunt said last month. “Frankly, I don’t think there are that many gaps to be filled in what happened on January 6th as it pertains to building security.”

RELATED: How a Capitol rioter cut his plea deal and what it means for others

It’s unclear what the Senate’s bipartisan report will mean for House Democratic leaders, who could decide in upcoming days and weeks to launch their own investigation either through a new Select Committee or through already established committees, which have been working on investigating the incidents surrounding January 6th for months.

Now that the report is out, the Senate Majority Leader Chuck Schumer could argue it does not go far enough and could force another vote to establish a commission. However, there still wouldn’t be the Republican votes to pass it. Without 60 votes or a united Democratic caucus willing to blow up the filibuster, a commission couldn’t be established.

This story has been updated with additional details from the report.

CNN’s Marshall Cohen contributed to this report.