The Senate Intelligence Committee has released its long-awaited bipartisan report on election security and Russian interference in the 2016 presidential election.

Among the key findings of the report, the committee writes that “the Russian government directed extensive activity, beginning in at least 2014 and carrying into at least 2017, against U.S. election infrastructure at the state and local level.”

The report is heavily redacted in some areas and is 67 pages. The Senate panel, which has been investigating Russian interference for more than two years, released a summary version of its election security findings in May 2018.

The panel released its redacted report one day after former special counsel Robert Mueller Robert (Bob) MuellerCNN's Toobin warns McCabe is in 'perilous condition' with emboldened Trump CNN anchor rips Trump over Stone while evoking Clinton-Lynch tarmac meeting The Hill's 12:30 Report: New Hampshire fallout MORE appeared on Capitol Hill to testify about his own 22-month investigation into Russian interference in the 2016 election and possible obstruction of justice by President Trump Donald John TrumpSteele Dossier sub-source was subject of FBI counterintelligence probe Pelosi slams Trump executive order on pre-existing conditions: It 'isn't worth the paper it's signed on' Trump 'no longer angry' at Romney because of Supreme Court stance MORE.

The congressional document, which is the product of a bipartisan investigation led by Senate Intelligence Committee Chairman Richard Burr Richard Mauze BurrHillicon Valley: Subpoenas for Facebook, Google and Twitter on the cards | Wray rebuffs mail-in voting conspiracies | Reps. raise mass surveillance concerns Bipartisan representatives demand answers on expired surveillance programs Rep. Mark Walker says he's been contacted about Liberty University vacancy MORE (R-N.C.) and Vice Chairman Mark Warner Mark Robert WarnerFBI director casts doubt on concerns over mail-in voting fraud Democrats call for declassifying election threats after briefing by Trump officials It's time to upgrade benefits MORE (D-Va.), recommended that officials give “renewed attention” to vulnerabilities in voting infrastructure, such as further securing voter registration databases.

The report also recommends that Congress should consider providing additional funding for states to secure elections once the $380 million appropriated by Congress to states for this purpose in 2018 is spent.

“In 2016, the U.S. was unprepared at all levels of government for a concerted attack from a determined foreign adversary on our election infrastructure,” Burr said in a statement, noting that the Department of Homeland Security and state and local election officials have made strides in the past three years “to bridge gaps in information sharing and shore up vulnerabilities.”

“There is still much work that remains to be done, however,” Burr said. “It is my hope that the Senate Intelligence Committee’s bipartisan report will provide the American people with valuable insight into the election security threats still facing our nation and the ways we can address them."

Warner echoed Burr, saying neither the federal government nor the states were “adequately prepared” when Russia attempted to infiltrate U.S. voting statements in 2016 but said they have taken steps since then to ensure election systems are better secured.

But, Warner added, “there’s still much more we can and must do to protect our elections.”

The panel is expected to release further volumes laying out the investigation’s findings regarding the intelligence community’s assessment, the Obama administration’s response to Russian interference, social media disinformation campaigns and whether there was coordination between the Trump campaign and Moscow sometime in the fall leading up to Election Day.

The report released Thursday stresses that federal agencies should remain “respectful” of state jurisdiction over the administration of elections, but that each should “be aware of their own cybersecurity limitations and know both how and when to obtain assistance.”

Mueller, during his highly anticipated testimony Wednesday, emphasized threats faced by U.S. elections from foreign interference.

“Over the course of my career, I've seen a number of challenges to our democracy,” Mueller said in his opening remarks. “The Russian government's effort to interfere in our election is among the most serious.”

Democrats seized on Mueller’s comments to try to pass multiple election security bills by unanimous consent in the Senate this week, including more funding for states to secure election systems, as well as one to require federal campaigns to report contact with foreign nationals to authorities.

However, Senate Republicans blocked each of these bills, with Majority Leader Mitch McConnell Addison (Mitch) Mitchell McConnellTrump 'no longer angry' at Romney because of Supreme Court stance On The Money: Anxious Democrats push for vote on COVID-19 aid | Pelosi, Mnuchin ready to restart talks | Weekly jobless claims increase | Senate treads close to shutdown deadline The Hill's Campaign Report: Trump faces backlash after not committing to peaceful transition of power MORE (R-Ky.) saying Thursday that he would only consider “bipartisan” legislation on the issue. McConnell has so far refused to allow a stand-alone vote on election security measures.

The Intelligence Committee’s report’s overall findings confirmed previous details made public about Russian efforts to access state voting infrastructure, with Illinois suffering the worst hit.

The committee reported that “as of the end of 2018, the Russian cyber actors had successfully penetrated Illinois's voter registration database, viewed multiple database tables, and accessed up to 200,000 voter registration records.” This attack led to the exfiltration of voter data including names, addresses, partial social security numbers, dates of birth and driver’s license numbers.

Election infrastructure in a second unnamed state was also breached, and several counties in that state were specifically probed. Officials from this state told the committee they were “highly confident” of the security of their systems, having implemented several upgrades since 2016.

While Illinois and the unnamed state suffered the worst effects of Russian election targeting, the committee wrote that intelligence developed in 2018 assessed that all 50 states were targeted in 2016 in some way.

The panel’s report cites testimony from Obama-era officials and Trump administration officials and security experts, as well as private interviews with state officials who are not named.

The Senate report says the investigation found no evidence any vote tallies were changed, vote-tallying systems manipulated or voter registration data changed or deleted but notes that the committee and the intelligence community’s insights are “limited.”

Mueller’s report, like the intelligence assessment that the Senate Intelligence Committee upheld, stated that Russia interfered to help Trump win but does not assert that Russia’s intervention had a material impact on the result of the election.

The Senate report also states that Russian Embassy officials submitted a request with the State Department to observe the election, which was not approved. Despite this, the committee found that the State Department was “aware that Russia was attempting to send election observers to polling places in 2016. The true intention of these efforts is unknown.”

The committee detailed Russian attempts to probe and access election systems and infrastructure in a variety of unnamed states. U.S. officials have said that Russian hackers probed election infrastructure in 21 states.

Among the more alarming of these finding was that in one state, cyber actors tried to penetrate systems that, had they been successful, would have allowed them to “manipulate the unofficial display of the election tallies.”

The report includes a number of recommendations. It calls on the federal government to create an effective deterrence by more forcefully pushing back on foreign interference, not only in the cyber arena, as part of a cyber doctrine.

“The United States should communicate to adversaries that it will view an attack on its election infrastructure as a hostile act, and we will respond accordingly. The U.S. Government should not limit its response to cyber activity; rather, it should create a menu of potential responses that will send a clear message and create significant costs for the perpetrator,” the report states.

It also includes a number of recommendations for federal and state officials to shore up the security of U.S. electoral systems, such as conducting security audits, institute two-factor authentication, create paper backups of voter databases and replace outdated voting systems.

The Senate panel opened its investigation in January 2017. Most of its work has taken place behind the scenes, as the committee has interviewed key members of the Trump campaign and other figures integral to the investigation.

Burr has at various points predicted the investigation to be wrapping up, but it has extended longer than anticipated. The committee was re-interviewing witnesses earlier this year, including Trump son-in-law and senior adviser Jared Kushner Jared Corey KushnerAbraham Accords: New hope for peace in Middle East Tenants in Kushner building file lawsuit alleging dangerous living conditions Trump hosts Israel, UAE, Bahrain for historic signing MORE and Donald Trump Jr. Don John Trump'Tiger King' star Joe Exotic requests pardon from Trump: 'Be my hero please' Zaid Jilani discusses Trump's move to cancel racial sensitivity training at federal agencies Trump International Hotel in Vancouver closes permanently MORE, who was summoned via subpoena.

Mueller’s investigation found that Russia interfered in the 2016 election in sweeping and systematic form, but did not find enough evidence to charge members of the Trump campaign in a broader conspiracy with Russia.

Mueller also did not reach a conclusion on whether Trump obstructed the Russia investigation — an issue of prime focus during the former special counsel’s testimony on Wednesday.

—Updated at 4:25 p.m.